This chapter discusses principles of solidification as they apply to pure metals. It examines mechanisms of solidification such as nucleation and growth, and applications like welding. The chapter outlines solidification processes, defects, and casting techniques. It provides examples calculating critical nucleation radius, redesigning a casting, and designing a riser. Diagrams of cooling curves and cast microstructures are also presented.
Bacillus cereus is a pathogenic bacteria that can cause two types of food poisoning - a diarrheal syndrome caused by an enterotoxin and an emetic syndrome caused by a emetic toxin. It grows well in temperatures from 10-50°C and pH values from 5-9. B. cereus food poisoning is usually mild and self-limiting but can be severe in immunocompromised individuals, and prevention focuses on proper food handling and storage to avoid bacterial growth.
IRJET- Quality Improvement of Ductile Iron Casting by Thermal AnalysisIRJET Journal
The document discusses using thermal analysis to improve the quality of ductile iron castings by reducing shrinkage defects. It presents the results of an experiment where cooling curves were recorded for ductile iron castings with different section thicknesses. Nine castings were produced with variations in chemical composition, inoculation amount, and pouring temperature. The cooling curves were analyzed to understand the solidification behavior and identify conditions that led to shrinkage. The results showed that thermal analysis is effective for controlling melt quality in ductile iron and avoiding shrinkage, with nil undercooling indicating sufficient inoculation for a given composition and thickness.
This document describes research into using additive manufacturing and investment casting to create sub-millimeter metal lattice structures. Stereolithography is used to create sacrificial scaffolds that are embedded in an investment matrix. The scaffolds are sublimated, leaving pores that are filled with ZAMAK alloy during casting. Two casting methods, spin casting and gravity casting with vacuum assist, are compared. Compression testing shows the two methods produce lattices with comparable mechanical strengths, demonstrating the viability of using these techniques to create sub-millimeter metal lattices.
This document summarizes a study on developing a full mould casting process using polystyrene foam as a pattern. A polystyrene cutting machine was fabricated to cut foam into patterns. An aluminum-silicon alloy was used for casting. Modification was done to improve mechanical properties. Tests found that the casting process produced parts with good shape, mechanical properties, and surface finish using the polystyrene foam pattern and modifier. The full mould casting process allows for complex shapes without draft or flash at lower cost, energy use, and waste compared to other casting methods.
Twin Roll Casting of Aluminum Alloy AC7A Using Commercial Scale MachineIJAEMSJORNAL
Twin roll casting process is able to produce a strip from molten metal directly. Thus this process has a possibility to reduce total cost of sheet making comparing to conventional rolling process. Strip casting process has some disadvantages. Casting speed depends on the material properties. It is difficult to determine the casting conditions. Twin roll casting of aluminum alloy AC7A using commercial scale machine was operated. The aims of this study is to investigate the effect of the roll speed. Continuous strip could not be produced at the roll speed 5 m/min. Continuous strip could be produced at the roll speed 10 m/min. However, cracks were observed. Continuous strip could be produced at the roll speed 20 m/min. However, cracks were observed too.
Analyzing the Effect of Alloying Addition in Steel samplesIRJET Journal
The document analyzes the effect of alloying titanium (Ti) in steel samples. Ti was added to low carbon steel samples in amounts of 0%, 0.3%, and 0.6% to study its effects. Hardness testing showed that hardness increased with higher Ti content due to Ti's ability to refine grains. Corrosion testing in sulfuric acid found that corrosion resistance improved with increasing Ti, as evidenced by more positive corrosion potentials and lower corrosion currents. Micrographs also showed less corrosion on surfaces of Ti-containing samples. In conclusion, the addition of Ti increased both the hardness and corrosion resistance of the low carbon steel samples.
Improving the properties of Ni-Based Alloys by Co AdditionIRJET Journal
1) The document discusses improving the properties of nickel-based alloys through the addition of cobalt.
2) Cobalt addition leads to grain refinement in the alloys, which influences both microstructure and corrosion resistance. Finer grain size improves hardness.
3) Samples of Ni-5Cr-5Al-xCo (where x is the cobalt content from 0-30%) were produced by vacuum arc melting and characterized through XRD, optical microscopy, and Vickers hardness testing.
4) Results showed that increasing the cobalt content refined grain size and improved hardness, while also enhancing corrosion resistance properties over the substrate material alone.
Bacillus cereus is a pathogenic bacteria that can cause two types of food poisoning - a diarrheal syndrome caused by an enterotoxin and an emetic syndrome caused by a emetic toxin. It grows well in temperatures from 10-50°C and pH values from 5-9. B. cereus food poisoning is usually mild and self-limiting but can be severe in immunocompromised individuals, and prevention focuses on proper food handling and storage to avoid bacterial growth.
IRJET- Quality Improvement of Ductile Iron Casting by Thermal AnalysisIRJET Journal
The document discusses using thermal analysis to improve the quality of ductile iron castings by reducing shrinkage defects. It presents the results of an experiment where cooling curves were recorded for ductile iron castings with different section thicknesses. Nine castings were produced with variations in chemical composition, inoculation amount, and pouring temperature. The cooling curves were analyzed to understand the solidification behavior and identify conditions that led to shrinkage. The results showed that thermal analysis is effective for controlling melt quality in ductile iron and avoiding shrinkage, with nil undercooling indicating sufficient inoculation for a given composition and thickness.
This document describes research into using additive manufacturing and investment casting to create sub-millimeter metal lattice structures. Stereolithography is used to create sacrificial scaffolds that are embedded in an investment matrix. The scaffolds are sublimated, leaving pores that are filled with ZAMAK alloy during casting. Two casting methods, spin casting and gravity casting with vacuum assist, are compared. Compression testing shows the two methods produce lattices with comparable mechanical strengths, demonstrating the viability of using these techniques to create sub-millimeter metal lattices.
This document summarizes a study on developing a full mould casting process using polystyrene foam as a pattern. A polystyrene cutting machine was fabricated to cut foam into patterns. An aluminum-silicon alloy was used for casting. Modification was done to improve mechanical properties. Tests found that the casting process produced parts with good shape, mechanical properties, and surface finish using the polystyrene foam pattern and modifier. The full mould casting process allows for complex shapes without draft or flash at lower cost, energy use, and waste compared to other casting methods.
Twin Roll Casting of Aluminum Alloy AC7A Using Commercial Scale MachineIJAEMSJORNAL
Twin roll casting process is able to produce a strip from molten metal directly. Thus this process has a possibility to reduce total cost of sheet making comparing to conventional rolling process. Strip casting process has some disadvantages. Casting speed depends on the material properties. It is difficult to determine the casting conditions. Twin roll casting of aluminum alloy AC7A using commercial scale machine was operated. The aims of this study is to investigate the effect of the roll speed. Continuous strip could not be produced at the roll speed 5 m/min. Continuous strip could be produced at the roll speed 10 m/min. However, cracks were observed. Continuous strip could be produced at the roll speed 20 m/min. However, cracks were observed too.
Analyzing the Effect of Alloying Addition in Steel samplesIRJET Journal
The document analyzes the effect of alloying titanium (Ti) in steel samples. Ti was added to low carbon steel samples in amounts of 0%, 0.3%, and 0.6% to study its effects. Hardness testing showed that hardness increased with higher Ti content due to Ti's ability to refine grains. Corrosion testing in sulfuric acid found that corrosion resistance improved with increasing Ti, as evidenced by more positive corrosion potentials and lower corrosion currents. Micrographs also showed less corrosion on surfaces of Ti-containing samples. In conclusion, the addition of Ti increased both the hardness and corrosion resistance of the low carbon steel samples.
Improving the properties of Ni-Based Alloys by Co AdditionIRJET Journal
1) The document discusses improving the properties of nickel-based alloys through the addition of cobalt.
2) Cobalt addition leads to grain refinement in the alloys, which influences both microstructure and corrosion resistance. Finer grain size improves hardness.
3) Samples of Ni-5Cr-5Al-xCo (where x is the cobalt content from 0-30%) were produced by vacuum arc melting and characterized through XRD, optical microscopy, and Vickers hardness testing.
4) Results showed that increasing the cobalt content refined grain size and improved hardness, while also enhancing corrosion resistance properties over the substrate material alone.
09C Processing and Applications of Ceramics (4.5 MB).pptssuser0cd0f1
This document contains 27 slides from an engineering materials lecture on non-metals and corrosion. The slides cover various topics including different classes of ceramics like glasses, clay products, refractories, abrasives, and cements. They describe ceramic properties, typical applications, processing methods, and how these materials are fabricated. The slides discuss techniques like powder pressing, sintering, tape casting, as well as drying and firing ceramics. Intended learning outcomes are provided which are to identify ceramic classes, understand their uses, describe processing differences from metals, and more.
09C Processing and Applications of Ceramics (4.5 MB).pptRamonaVintila
This document contains 29 slides summarizing ceramic materials, processing, and applications. It begins with an overview of different classes of ceramics including their properties and typical uses. Processing techniques for ceramics are then discussed, such as glass forming, powder pressing, sintering, and tape casting. Specific fabrication methods for different ceramic types like clay products and abrasives are also outlined. The document concludes with a summary slide emphasizing that ceramics are classified based on both their structure and applications, and can be processed as either glasses or powders depending on the technique.
Experimental Investigation on Effect of Curtailed reinforcement in R.C beamsIRJET Journal
The document experimentally investigates the effect of curtailed reinforcement in reinforced concrete beams. Six beams were cast - three with curtailed reinforcement and three without. The beams were subjected to static compressive loading. Beams with curtailed reinforcement showed similar deflection levels to those without curtailment, while using 10.65% less steel. Cracks developed earlier in beams with curtailed reinforcement, but failure modes were similar between beam types. In conclusion, curtailed reinforcement can reduce steel usage without compromising structural performance, providing a more cost-effective design.
1) Shell mold casting is a metal casting process where a mold is made from a thin-walled shell created by applying a sand-resin mixture around a pattern. This allows for higher production rates and more complex geometries compared to sand casting.
2) The process involves creating a reusable metal pattern, heating it, and applying a sand-resin mixture to form a shell mold around the pattern. The shells are then cured, filled with molten metal, and broken to remove the casting.
3) Shell mold casting provides advantages like high dimensional accuracy, automation potential, fewer gas defects, and lower labor costs compared to sand casting. It is often used for small to medium parts requiring precision.
Experimental Investigation on Composite Slab using Cold Formed Steel Sheet in...ijtsrd
1. The study experimentally investigates the load carrying capacity of composite slabs made with cold formed steel sheets and different types of concrete.
2. Three geometric profile shapes of steel decking were tested: trapezoidal, rectangular, and holorib. Concretes tested included reinforced cement concrete, foam concrete, and fiber reinforced concrete.
3. Test results showed that composite slabs with rectangular profile steel sheets without embossments had the highest load carrying capacity. Rectangular profiled slabs also performed better than trapezoidal or re-entrant profiled slabs. Lightweight concrete with expanded clay aggregates performed similarly to normal concrete.
The document summarizes a research project examining a hybrid metal matrix composite combining alumina, zirconia, and titanium. The objectives are to determine an optimal composition, sintering temperature, and mechanical properties including strength, hardness, wear resistance, and temperature resistance. Samples will be prepared by ball milling and pressing the materials, then sintered and tested using water jet machining to determine removal rate, grain structure changes, and surface roughness under different parameters. The project aims to develop a material suitable for applications in nuclear reactors, turbine blades, and advanced engines. Testing will take place at VB Ceramics in Chennai, India.
This document discusses hot tear defects in castings and methods to prevent them. It provides the following key points:
- Hot tears occur during solidification due to resistance to contraction from molds/cores and uneven temperature gradients. Two conditions are needed - resistance to contraction and variable temperature gradients.
- Preventing methods include using strong molds that collapse slowly, designing castings with uniform thickness, adding chills or ribs to promote faster cooling, and controlling steel chemistry to reduce hydrogen and sulfur levels.
- Case studies using computer simulations show locations of hot zones in castings and how positioning chills or changing mold materials reduces temperatures and prevents hot tears.
Manufacturing of liquid propellant tankSai Malleswar
The document discusses the manufacturing process of liquid propellant tanks used in rockets. It describes the key design requirements, including withstanding pressure while being lightweight. The tanks are made of aluminum alloy and consist of domes, cylindrical shells, and other components joined by welding. The manufacturing processes for each component are detailed, including forging, drilling, welding, rolling, and hydroforming. The complete tank assembly process is also outlined.
This document summarizes a research article that proposes a new rapid prototyping process called composite metal foil manufacturing (CMFM). CMFM combines laminated object manufacturing and soldering techniques to produce high-quality metal parts directly from CAD models using thin metal foils and solder paste. The researchers developed an experimental setup to demonstrate CMFM and produced test specimens from copper foil. They then evaluated the specimens using lap-shear testing, peel testing, microstructural analysis, and comparison to other methods to validate the effectiveness of CMFM for producing metal prototypes.
Adding rhenium to the binder in cemented carbide finalEyvind Engblom
The document discusses adding rhenium (Re) to the cobalt (Co) binder phase in cemented carbides. Two samples were investigated - one containing tungsten carbide (WC), cobalt, and rhenium (WC-Co-Re), and one reference sample containing just WC and Co (WC-Co).
The WC-Co-Re sample showed an increase in hardness of 150 MPa compared to the reference sample. Scanning electron microscopy and electron dispersive x-ray spectroscopy analysis revealed that the rhenium dissolved together with the cobalt in the binder phase.
The aim of adding rhenium was to improve the high-temperature properties of the cobalt binder by
This document discusses the materials and manufacturing process used for the Brodie steel helmet from World War 1. It then evaluates potential alternative materials for military helmets.
The Brodie helmet was made of Hadfield steel through a deep drawing process to form its distinctive shape. This provided ballistic protection from shrapnel through a combination of hardness from work hardening during forming and toughness in the inner layer. However, steel helmets are heavy, can transmit impact forces, and are susceptible to corrosion.
The document then evaluates properties required for helmet materials, including energy absorption capacity. Carbon fiber composites and boron carbide are identified as alternatives with advantages over steel such as lower weight and ability to dissipate impacts without
Experimental Investigation on Replacement of Magnetic Water and Partial Repla...IRJET Journal
This document experimentally investigates replacing magnetic water and steel slag as a partial replacement for coarse aggregate in concrete. Three mixtures were tested with 50%, 60%, and 70% steel slag replacing coarse aggregate. Compressive strength, split tensile strength, and flexural strength were tested at 7, 14, and 28 days. Results showed that compressive strength increased up to 1.87% and flexural strength increased up to 1.2% compared to conventional concrete. Using magnetic water and steel slag provided improved strength properties over conventional concrete. The study concluded that 60-70% steel slag with magnetic water replacement can provide higher strengths for concrete.
Mechanism of Fracture in Friction Stir Processed Aluminium AlloyDr. Amarjeet Singh
Aluminium alloys are used for important
applications in reducing the weight of the component and
structure particularly associated with transport, marine,
and aerospace fields. Grain refinement by scandium (Sc)
addition can eliminate the casting defects and increase the
resistance to hot tearing for high strength aluminium alloys.
FSP for cast aluminium alloys have been focused and it has
great advantages including solid state microstructural
evolution, altering mechanical properties by optimizing
process parameters. These parameters are tool rotational
speeds (720, and 1000 rpm), traverse speeds (80, and 70
mm/min), and axial compressive force at 15 kN, etc. The
mechanical properties had been evaluated on FSPed
aluminium alloy with different microstructural conditions.
Fracture properties of aluminium alloys are very important
for industrial applications. Tensile and fracture toughness
properties were correlated to microstructural and
fractographic features of the aluminium alloys need to
explore their essential failure mechanisms.
This document provides an overview of Chapter 14 from a materials science textbook on ceramic materials. The chapter discusses the synthesis, processing, and applications of ceramics including inorganic glasses and glass-ceramics. It begins with the objectives and outline of topics to be covered, which include properties of ceramics, synthesis of ceramic powders, powder processing techniques, characteristics of sintered ceramics, inorganic glasses, glass-ceramics, clay products, refractories and other ceramic materials. Examples are provided to illustrate ceramic formulation and processing techniques. The document contains diagrams and tables to supplement the textual explanations.
Corrosion resistance performance of fly ash blended cement concreteseSAT Journals
Abstract Durability of reinforced concrete with respect to corrosion of reinforcement is one of the major aspects to be considered in the management of civil infrastructure systems. An accelerated laboratory test method developed at SERC where the concrete specimen containing rebar is subjected to polarization under a constant voltage in a sodium chloride solution. It is found that the current response with time follows that of a typical service life model indicating depassivation and corrosion propagation. Index terms- Materials, cement, super plasticizer, workability, compressive strength etc.
Corrosion resistance performance of fly ash blended cement concreteseSAT Publishing House
1) The document describes an experimental study on the corrosion resistance of reinforced concrete with different percentages of fly ash replacement.
2) An accelerated corrosion test method was used where concrete cylinders containing rebar were subjected to polarization in a sodium chloride solution. This simulated rebar corrosion in marine environments.
3) The test results showed that concretes with 30% fly ash replacement had the highest corrosion resistance, with initiation times of 54 and 63 days for M25 and M30 grade concrete, respectively.
4) Graphs of current over time showed changes in slope indicating the initiation time and time for cracking, which increased with higher percentages of fly ash replacement up to 30%.
IRJET- A Review Paper on Light Weight Autoclave Aerated Concrete BlockIRJET Journal
This document provides a review of light weight autoclave aerated concrete blocks. It discusses the manufacturing process, which involves mixing raw materials like cement, water, fly ash, lime, and aluminum powder. The mixture is cured in an autoclave under high temperature and pressure to produce lightweight blocks containing 50-60% air. Tests showed the blocks have low water absorption, compressive strength of 3.78 N/mm2, and flexural strength of 0.69 N/mm2. AAC blocks offer benefits like lighter weight, lower costs, better seismic and fire performance than clay bricks. The document concludes AAC is a sustainable and eco-friendly building material.
. One of the methods used to surface hardening of ductile iron is chilled cast iron. Chill as the fast cooling rate in the mold during solidification and chill thickness greatly affects the thickness of the hardness layer. The main material used is ductile iron, and the chill material is SS 304. Casting uses the sand casting method. Before pouring, the chill plate has been inserted onto the surface of the pattern that has been formed in the mold, then the chill plate is preheated at 700OC. Pouring was carried out at a melting temperature of 1400OC, and then cooled with argon and O2 sprays into the mold in solidification conditions at exactly 700OC. The results analyzed were the microstructure, hardness value, and the hardness of the thickness layer. This chill coolant will absorb heat very quickly and the Cr and Ni alloy will diffuse to the specimen surface to stabilize the ferrite and austenite phases in the final solidification. The particles on the hard surface have Ferro carbide M7C3, which is in the form of cementite and martensitic phases so that to categorized as white cast iron structure formed on the surface with an area around 1.5-3mm has a hardness of 61-65HRC. But in the center area is 31-49HRC
IRJET- Experimental Study of Structural Behaviour of Double Skin Hollow –...IRJET Journal
This document summarizes an experimental study on the structural behavior of double skin hollow concrete filled steel tubular (DSH-CFST) columns under axial compressive loading. 36 specimens were tested with varying hollowness ratios. Test results showed that DSH-CFST columns can provide higher strength and ductility than solid CFST columns. Stress-strain curves and load-deformation curves were compared for different specimen types. The study found that DSH-CFST columns exhibited up to 77% higher compressive stresses than solid CFST columns. DSH-CFST columns also demonstrated improved ductility compared to solid CFST columns. The results provide information on optimizing the strength and structural performance of DSH-CFST columns
Investigation on Flexural Behaviour of Cold Formed Latticed Built-Up BeamDr. Amarjeet Singh
There are two structural members used in steel construction the hot rolled members and the cold formed members. They are light members compared to the traditional heavier hot rolled steel structural members used in the field. They have high strength to weight ratio resulting in less dead weight making it a good option in construction of bridges roof trusses transmission line towers multi storied buildings and other structural members. This paper is done to understand the flexural capacity and to enhance it by developing innovative latticed cold formed steel beam. The impact of web opening of the cold formed beam on the flexural behavior of cold formed built-up I section under two point loading is investigated for the simply supported end conditions. Numerical analysis is performed using finite element analysis (FEM) software. From results, the load vs. Deflection curve, failure modes and ultimate load carrying capacity of the specimen presented in this paper. Therefore the main focus of this project is to investigate the flexural behavior of these steel members and by replacing the lattice hot rolled section by cold formed steel sections. The ultimate load carrying capacity with failure mode of simulated FEA models was compared with experimental results.
ACEP Magazine edition 4th launched on 05.06.2024Rahul
This document provides information about the third edition of the magazine "Sthapatya" published by the Association of Civil Engineers (Practicing) Aurangabad. It includes messages from current and past presidents of ACEP, memories and photos from past ACEP events, information on life time achievement awards given by ACEP, and a technical article on concrete maintenance, repairs and strengthening. The document highlights activities of ACEP and provides a technical educational article for members.
09C Processing and Applications of Ceramics (4.5 MB).pptssuser0cd0f1
This document contains 27 slides from an engineering materials lecture on non-metals and corrosion. The slides cover various topics including different classes of ceramics like glasses, clay products, refractories, abrasives, and cements. They describe ceramic properties, typical applications, processing methods, and how these materials are fabricated. The slides discuss techniques like powder pressing, sintering, tape casting, as well as drying and firing ceramics. Intended learning outcomes are provided which are to identify ceramic classes, understand their uses, describe processing differences from metals, and more.
09C Processing and Applications of Ceramics (4.5 MB).pptRamonaVintila
This document contains 29 slides summarizing ceramic materials, processing, and applications. It begins with an overview of different classes of ceramics including their properties and typical uses. Processing techniques for ceramics are then discussed, such as glass forming, powder pressing, sintering, and tape casting. Specific fabrication methods for different ceramic types like clay products and abrasives are also outlined. The document concludes with a summary slide emphasizing that ceramics are classified based on both their structure and applications, and can be processed as either glasses or powders depending on the technique.
Experimental Investigation on Effect of Curtailed reinforcement in R.C beamsIRJET Journal
The document experimentally investigates the effect of curtailed reinforcement in reinforced concrete beams. Six beams were cast - three with curtailed reinforcement and three without. The beams were subjected to static compressive loading. Beams with curtailed reinforcement showed similar deflection levels to those without curtailment, while using 10.65% less steel. Cracks developed earlier in beams with curtailed reinforcement, but failure modes were similar between beam types. In conclusion, curtailed reinforcement can reduce steel usage without compromising structural performance, providing a more cost-effective design.
1) Shell mold casting is a metal casting process where a mold is made from a thin-walled shell created by applying a sand-resin mixture around a pattern. This allows for higher production rates and more complex geometries compared to sand casting.
2) The process involves creating a reusable metal pattern, heating it, and applying a sand-resin mixture to form a shell mold around the pattern. The shells are then cured, filled with molten metal, and broken to remove the casting.
3) Shell mold casting provides advantages like high dimensional accuracy, automation potential, fewer gas defects, and lower labor costs compared to sand casting. It is often used for small to medium parts requiring precision.
Experimental Investigation on Composite Slab using Cold Formed Steel Sheet in...ijtsrd
1. The study experimentally investigates the load carrying capacity of composite slabs made with cold formed steel sheets and different types of concrete.
2. Three geometric profile shapes of steel decking were tested: trapezoidal, rectangular, and holorib. Concretes tested included reinforced cement concrete, foam concrete, and fiber reinforced concrete.
3. Test results showed that composite slabs with rectangular profile steel sheets without embossments had the highest load carrying capacity. Rectangular profiled slabs also performed better than trapezoidal or re-entrant profiled slabs. Lightweight concrete with expanded clay aggregates performed similarly to normal concrete.
The document summarizes a research project examining a hybrid metal matrix composite combining alumina, zirconia, and titanium. The objectives are to determine an optimal composition, sintering temperature, and mechanical properties including strength, hardness, wear resistance, and temperature resistance. Samples will be prepared by ball milling and pressing the materials, then sintered and tested using water jet machining to determine removal rate, grain structure changes, and surface roughness under different parameters. The project aims to develop a material suitable for applications in nuclear reactors, turbine blades, and advanced engines. Testing will take place at VB Ceramics in Chennai, India.
This document discusses hot tear defects in castings and methods to prevent them. It provides the following key points:
- Hot tears occur during solidification due to resistance to contraction from molds/cores and uneven temperature gradients. Two conditions are needed - resistance to contraction and variable temperature gradients.
- Preventing methods include using strong molds that collapse slowly, designing castings with uniform thickness, adding chills or ribs to promote faster cooling, and controlling steel chemistry to reduce hydrogen and sulfur levels.
- Case studies using computer simulations show locations of hot zones in castings and how positioning chills or changing mold materials reduces temperatures and prevents hot tears.
Manufacturing of liquid propellant tankSai Malleswar
The document discusses the manufacturing process of liquid propellant tanks used in rockets. It describes the key design requirements, including withstanding pressure while being lightweight. The tanks are made of aluminum alloy and consist of domes, cylindrical shells, and other components joined by welding. The manufacturing processes for each component are detailed, including forging, drilling, welding, rolling, and hydroforming. The complete tank assembly process is also outlined.
This document summarizes a research article that proposes a new rapid prototyping process called composite metal foil manufacturing (CMFM). CMFM combines laminated object manufacturing and soldering techniques to produce high-quality metal parts directly from CAD models using thin metal foils and solder paste. The researchers developed an experimental setup to demonstrate CMFM and produced test specimens from copper foil. They then evaluated the specimens using lap-shear testing, peel testing, microstructural analysis, and comparison to other methods to validate the effectiveness of CMFM for producing metal prototypes.
Adding rhenium to the binder in cemented carbide finalEyvind Engblom
The document discusses adding rhenium (Re) to the cobalt (Co) binder phase in cemented carbides. Two samples were investigated - one containing tungsten carbide (WC), cobalt, and rhenium (WC-Co-Re), and one reference sample containing just WC and Co (WC-Co).
The WC-Co-Re sample showed an increase in hardness of 150 MPa compared to the reference sample. Scanning electron microscopy and electron dispersive x-ray spectroscopy analysis revealed that the rhenium dissolved together with the cobalt in the binder phase.
The aim of adding rhenium was to improve the high-temperature properties of the cobalt binder by
This document discusses the materials and manufacturing process used for the Brodie steel helmet from World War 1. It then evaluates potential alternative materials for military helmets.
The Brodie helmet was made of Hadfield steel through a deep drawing process to form its distinctive shape. This provided ballistic protection from shrapnel through a combination of hardness from work hardening during forming and toughness in the inner layer. However, steel helmets are heavy, can transmit impact forces, and are susceptible to corrosion.
The document then evaluates properties required for helmet materials, including energy absorption capacity. Carbon fiber composites and boron carbide are identified as alternatives with advantages over steel such as lower weight and ability to dissipate impacts without
Experimental Investigation on Replacement of Magnetic Water and Partial Repla...IRJET Journal
This document experimentally investigates replacing magnetic water and steel slag as a partial replacement for coarse aggregate in concrete. Three mixtures were tested with 50%, 60%, and 70% steel slag replacing coarse aggregate. Compressive strength, split tensile strength, and flexural strength were tested at 7, 14, and 28 days. Results showed that compressive strength increased up to 1.87% and flexural strength increased up to 1.2% compared to conventional concrete. Using magnetic water and steel slag provided improved strength properties over conventional concrete. The study concluded that 60-70% steel slag with magnetic water replacement can provide higher strengths for concrete.
Mechanism of Fracture in Friction Stir Processed Aluminium AlloyDr. Amarjeet Singh
Aluminium alloys are used for important
applications in reducing the weight of the component and
structure particularly associated with transport, marine,
and aerospace fields. Grain refinement by scandium (Sc)
addition can eliminate the casting defects and increase the
resistance to hot tearing for high strength aluminium alloys.
FSP for cast aluminium alloys have been focused and it has
great advantages including solid state microstructural
evolution, altering mechanical properties by optimizing
process parameters. These parameters are tool rotational
speeds (720, and 1000 rpm), traverse speeds (80, and 70
mm/min), and axial compressive force at 15 kN, etc. The
mechanical properties had been evaluated on FSPed
aluminium alloy with different microstructural conditions.
Fracture properties of aluminium alloys are very important
for industrial applications. Tensile and fracture toughness
properties were correlated to microstructural and
fractographic features of the aluminium alloys need to
explore their essential failure mechanisms.
This document provides an overview of Chapter 14 from a materials science textbook on ceramic materials. The chapter discusses the synthesis, processing, and applications of ceramics including inorganic glasses and glass-ceramics. It begins with the objectives and outline of topics to be covered, which include properties of ceramics, synthesis of ceramic powders, powder processing techniques, characteristics of sintered ceramics, inorganic glasses, glass-ceramics, clay products, refractories and other ceramic materials. Examples are provided to illustrate ceramic formulation and processing techniques. The document contains diagrams and tables to supplement the textual explanations.
Corrosion resistance performance of fly ash blended cement concreteseSAT Journals
Abstract Durability of reinforced concrete with respect to corrosion of reinforcement is one of the major aspects to be considered in the management of civil infrastructure systems. An accelerated laboratory test method developed at SERC where the concrete specimen containing rebar is subjected to polarization under a constant voltage in a sodium chloride solution. It is found that the current response with time follows that of a typical service life model indicating depassivation and corrosion propagation. Index terms- Materials, cement, super plasticizer, workability, compressive strength etc.
Corrosion resistance performance of fly ash blended cement concreteseSAT Publishing House
1) The document describes an experimental study on the corrosion resistance of reinforced concrete with different percentages of fly ash replacement.
2) An accelerated corrosion test method was used where concrete cylinders containing rebar were subjected to polarization in a sodium chloride solution. This simulated rebar corrosion in marine environments.
3) The test results showed that concretes with 30% fly ash replacement had the highest corrosion resistance, with initiation times of 54 and 63 days for M25 and M30 grade concrete, respectively.
4) Graphs of current over time showed changes in slope indicating the initiation time and time for cracking, which increased with higher percentages of fly ash replacement up to 30%.
IRJET- A Review Paper on Light Weight Autoclave Aerated Concrete BlockIRJET Journal
This document provides a review of light weight autoclave aerated concrete blocks. It discusses the manufacturing process, which involves mixing raw materials like cement, water, fly ash, lime, and aluminum powder. The mixture is cured in an autoclave under high temperature and pressure to produce lightweight blocks containing 50-60% air. Tests showed the blocks have low water absorption, compressive strength of 3.78 N/mm2, and flexural strength of 0.69 N/mm2. AAC blocks offer benefits like lighter weight, lower costs, better seismic and fire performance than clay bricks. The document concludes AAC is a sustainable and eco-friendly building material.
. One of the methods used to surface hardening of ductile iron is chilled cast iron. Chill as the fast cooling rate in the mold during solidification and chill thickness greatly affects the thickness of the hardness layer. The main material used is ductile iron, and the chill material is SS 304. Casting uses the sand casting method. Before pouring, the chill plate has been inserted onto the surface of the pattern that has been formed in the mold, then the chill plate is preheated at 700OC. Pouring was carried out at a melting temperature of 1400OC, and then cooled with argon and O2 sprays into the mold in solidification conditions at exactly 700OC. The results analyzed were the microstructure, hardness value, and the hardness of the thickness layer. This chill coolant will absorb heat very quickly and the Cr and Ni alloy will diffuse to the specimen surface to stabilize the ferrite and austenite phases in the final solidification. The particles on the hard surface have Ferro carbide M7C3, which is in the form of cementite and martensitic phases so that to categorized as white cast iron structure formed on the surface with an area around 1.5-3mm has a hardness of 61-65HRC. But in the center area is 31-49HRC
IRJET- Experimental Study of Structural Behaviour of Double Skin Hollow –...IRJET Journal
This document summarizes an experimental study on the structural behavior of double skin hollow concrete filled steel tubular (DSH-CFST) columns under axial compressive loading. 36 specimens were tested with varying hollowness ratios. Test results showed that DSH-CFST columns can provide higher strength and ductility than solid CFST columns. Stress-strain curves and load-deformation curves were compared for different specimen types. The study found that DSH-CFST columns exhibited up to 77% higher compressive stresses than solid CFST columns. DSH-CFST columns also demonstrated improved ductility compared to solid CFST columns. The results provide information on optimizing the strength and structural performance of DSH-CFST columns
Investigation on Flexural Behaviour of Cold Formed Latticed Built-Up BeamDr. Amarjeet Singh
There are two structural members used in steel construction the hot rolled members and the cold formed members. They are light members compared to the traditional heavier hot rolled steel structural members used in the field. They have high strength to weight ratio resulting in less dead weight making it a good option in construction of bridges roof trusses transmission line towers multi storied buildings and other structural members. This paper is done to understand the flexural capacity and to enhance it by developing innovative latticed cold formed steel beam. The impact of web opening of the cold formed beam on the flexural behavior of cold formed built-up I section under two point loading is investigated for the simply supported end conditions. Numerical analysis is performed using finite element analysis (FEM) software. From results, the load vs. Deflection curve, failure modes and ultimate load carrying capacity of the specimen presented in this paper. Therefore the main focus of this project is to investigate the flexural behavior of these steel members and by replacing the lattice hot rolled section by cold formed steel sections. The ultimate load carrying capacity with failure mode of simulated FEA models was compared with experimental results.
ACEP Magazine edition 4th launched on 05.06.2024Rahul
This document provides information about the third edition of the magazine "Sthapatya" published by the Association of Civil Engineers (Practicing) Aurangabad. It includes messages from current and past presidents of ACEP, memories and photos from past ACEP events, information on life time achievement awards given by ACEP, and a technical article on concrete maintenance, repairs and strengthening. The document highlights activities of ACEP and provides a technical educational article for members.
Literature Review Basics and Understanding Reference Management.pptxDr Ramhari Poudyal
Three-day training on academic research focuses on analytical tools at United Technical College, supported by the University Grant Commission, Nepal. 24-26 May 2024
DEEP LEARNING FOR SMART GRID INTRUSION DETECTION: A HYBRID CNN-LSTM-BASED MODELgerogepatton
As digital technology becomes more deeply embedded in power systems, protecting the communication
networks of Smart Grids (SG) has emerged as a critical concern. Distributed Network Protocol 3 (DNP3)
represents a multi-tiered application layer protocol extensively utilized in Supervisory Control and Data
Acquisition (SCADA)-based smart grids to facilitate real-time data gathering and control functionalities.
Robust Intrusion Detection Systems (IDS) are necessary for early threat detection and mitigation because
of the interconnection of these networks, which makes them vulnerable to a variety of cyberattacks. To
solve this issue, this paper develops a hybrid Deep Learning (DL) model specifically designed for intrusion
detection in smart grids. The proposed approach is a combination of the Convolutional Neural Network
(CNN) and the Long-Short-Term Memory algorithms (LSTM). We employed a recent intrusion detection
dataset (DNP3), which focuses on unauthorized commands and Denial of Service (DoS) cyberattacks, to
train and test our model. The results of our experiments show that our CNN-LSTM method is much better
at finding smart grid intrusions than other deep learning algorithms used for classification. In addition,
our proposed approach improves accuracy, precision, recall, and F1 score, achieving a high detection
accuracy rate of 99.50%.
Harnessing WebAssembly for Real-time Stateless Streaming PipelinesChristina Lin
Traditionally, dealing with real-time data pipelines has involved significant overhead, even for straightforward tasks like data transformation or masking. However, in this talk, we’ll venture into the dynamic realm of WebAssembly (WASM) and discover how it can revolutionize the creation of stateless streaming pipelines within a Kafka (Redpanda) broker. These pipelines are adept at managing low-latency, high-data-volume scenarios.
Presentation of IEEE Slovenia CIS (Computational Intelligence Society) Chapte...University of Maribor
Slides from talk presenting:
Aleš Zamuda: Presentation of IEEE Slovenia CIS (Computational Intelligence Society) Chapter and Networking.
Presentation at IcETRAN 2024 session:
"Inter-Society Networking Panel GRSS/MTT-S/CIS
Panel Session: Promoting Connection and Cooperation"
IEEE Slovenia GRSS
IEEE Serbia and Montenegro MTT-S
IEEE Slovenia CIS
11TH INTERNATIONAL CONFERENCE ON ELECTRICAL, ELECTRONIC AND COMPUTING ENGINEERING
3-6 June 2024, Niš, Serbia
Advanced control scheme of doubly fed induction generator for wind turbine us...IJECEIAES
This paper describes a speed control device for generating electrical energy on an electricity network based on the doubly fed induction generator (DFIG) used for wind power conversion systems. At first, a double-fed induction generator model was constructed. A control law is formulated to govern the flow of energy between the stator of a DFIG and the energy network using three types of controllers: proportional integral (PI), sliding mode controller (SMC) and second order sliding mode controller (SOSMC). Their different results in terms of power reference tracking, reaction to unexpected speed fluctuations, sensitivity to perturbations, and resilience against machine parameter alterations are compared. MATLAB/Simulink was used to conduct the simulations for the preceding study. Multiple simulations have shown very satisfying results, and the investigations demonstrate the efficacy and power-enhancing capabilities of the suggested control system.
A SYSTEMATIC RISK ASSESSMENT APPROACH FOR SECURING THE SMART IRRIGATION SYSTEMSIJNSA Journal
The smart irrigation system represents an innovative approach to optimize water usage in agricultural and landscaping practices. The integration of cutting-edge technologies, including sensors, actuators, and data analysis, empowers this system to provide accurate monitoring and control of irrigation processes by leveraging real-time environmental conditions. The main objective of a smart irrigation system is to optimize water efficiency, minimize expenses, and foster the adoption of sustainable water management methods. This paper conducts a systematic risk assessment by exploring the key components/assets and their functionalities in the smart irrigation system. The crucial role of sensors in gathering data on soil moisture, weather patterns, and plant well-being is emphasized in this system. These sensors enable intelligent decision-making in irrigation scheduling and water distribution, leading to enhanced water efficiency and sustainable water management practices. Actuators enable automated control of irrigation devices, ensuring precise and targeted water delivery to plants. Additionally, the paper addresses the potential threat and vulnerabilities associated with smart irrigation systems. It discusses limitations of the system, such as power constraints and computational capabilities, and calculates the potential security risks. The paper suggests possible risk treatment methods for effective secure system operation. In conclusion, the paper emphasizes the significant benefits of implementing smart irrigation systems, including improved water conservation, increased crop yield, and reduced environmental impact. Additionally, based on the security analysis conducted, the paper recommends the implementation of countermeasures and security approaches to address vulnerabilities and ensure the integrity and reliability of the system. By incorporating these measures, smart irrigation technology can revolutionize water management practices in agriculture, promoting sustainability, resource efficiency, and safeguarding against potential security threats.
International Conference on NLP, Artificial Intelligence, Machine Learning an...gerogepatton
International Conference on NLP, Artificial Intelligence, Machine Learning and Applications (NLAIM 2024) offers a premier global platform for exchanging insights and findings in the theory, methodology, and applications of NLP, Artificial Intelligence, Machine Learning, and their applications. The conference seeks substantial contributions across all key domains of NLP, Artificial Intelligence, Machine Learning, and their practical applications, aiming to foster both theoretical advancements and real-world implementations. With a focus on facilitating collaboration between researchers and practitioners from academia and industry, the conference serves as a nexus for sharing the latest developments in the field.
KuberTENes Birthday Bash Guadalajara - K8sGPT first impressionsVictor Morales
K8sGPT is a tool that analyzes and diagnoses Kubernetes clusters. This presentation was used to share the requirements and dependencies to deploy K8sGPT in a local environment.
KuberTENes Birthday Bash Guadalajara - K8sGPT first impressions
4457301.ppt
1. 1 1
The Science and Engineering
of Materials, 4th ed
Donald R. Askeland – Pradeep P. Phulé
Chapter 8 – Principles of Solidification
2. 2
2
Objectives of Chapter 8
Study the principles of solidification
as they apply to pure metals.
Examine the mechanisms by which
solidification occurs.
Examine how techniques such as
welding, brazing, and soldering are
used for joining metals.
4. 4
4
8.9 Casting Processes for
Manufacturing Components
8.10 Continuous Casting and Ingot
Casting
8.11 Directional Solidification (DS),
Single Crystal Growth, and
Epitaxial Growth
8.12 Solidification of Polymers and
Inorganic Glasses
8.13 Joining of Metallic Materials
Chapter Outline (Continued)
5. 5
5
Primary processing - Processes involving casting of
molten metals into ingots or semi-finished useful shapes
such as slabs.
Secondary processing - Processes such as rolling,
extrusion, etc.used to process ingots or slabs and other
semi-finished shapes.
Section 8.1 Technological
Significance
6. 6
6
Figure 8.1 An image of a
bronze object. This Canteen
(bian hu) from China, Warring
States period, circa 3rd
century BCE (bronze inlaid
with silver). (Courtesy of
Freer Gallery of Art,
Smithsonian Institution,
Washington, D.C.)
Figure 8.2 (a) Aluminum alloy
wheels for automotives, (b)
optical fibers for communication.
(Courtesy of PhotoDisc/Getty
Images.)
7. 7
7
Nucleation - The physical process by which a new phase
is produced in a material.
Critical radius (r*) - The minimum size that must be
formed by atoms clustering together in the liquid before
the solid particle is stable and begins to grow.
Undercooling - The temperature to which the liquid metal
must cool below the equilibrium freezing temperature
before nucleation occurs.
Homogeneous nucleation - Formation of a critically sized
solid from the liquid by the clustering together of a large
number of atoms at a high undercooling (without an
external interface).
Heterogeneous nucleation - Formation of a critically
sized solid from the liquid on an impurity surface.
Section 8.2 Nucleation
11. 11
11
Calculate the size of the critical radius and the number of
atoms in the critical nucleus when solid copper forms by
homogeneous nucleation. Comment on the size of the nucleus
and assumptions we made while deriving the equation for
radius of nucleus.
Example 8.1 SOLUTION
Example 8.1
Calculation of Critical Radius for the
Solidification of Copper
15. 15
15
Grain refinement - The addition of heterogeneous nuclei
in a controlled manner to increase the number of grains
in a casting.
Dispersion strengthening - Increase in strength of a
metallic material by generating resistance to dislocation
motion by the introduction of small clusters of a second
material.
Solid-state phase transformation - A change in phase
that occurs in the solid state.
Rapid solidification processing - Producing unique
material structures by promoting unusually high cooling
rates during solidification.
Section 8.3 Applications of
Controlled Nucleation
16. 16
16
Specific heat - The heat required to change the
temperature of a unit weight of the material one degree.
Solidification front - Interface between a solid and liquid.
Planar growth - The growth of a smooth solid-liquid
interface during solidification, when no undercooling of
the liquid is present.
Dendrite - The treelike structure of the solid that grows
when an undercooled liquid solidifies.
Section 8.4 Growth Mechanisms
19. 19
19
Chvorinov’s rule - The solidification time of a casting is
directly proportional to the square of the volume-to-
surface area ratio of the casting.
Mold constant (B) - A characteristic constant in
Chvorinov’s rule.
Secondary dendrite arm spacing (SDAS) - The distance
between the centers of two adjacent secondary dendrite
arms.
Section 8.5 Solidification Time and
Dendrite Size
20. 20
20
Your company currently is producing a disk-shaped brass
casting 2 in. thick and 18 in.in diameter. You believe that
by making the casting solidify 25% faster, the
improvement in the tensile properties of the casting will
permit the casting to be made lighter in weight. Design
the casting to permit this.Assume that the mold constant
is 22 min/in.2 for this process.
Example 8.2
Redesign of a Casting for Improved
Strength
21. 21
21
Example 8.2 SOLUTION
If d is the diameter and x is the thickness of the casting,
then the volume, surface area, and solidification time of
the 2-in.thick casting are:
22. 22
22
Example 8.2 SOLUTION (Continued)
Since the casting conditions have not changed, the mold
constant B is unchanged. The V/A ratio of the new casting
is:
23. 23
23
Figure 8.9 (a) The secondary dendrite arm spacing
(SDAS). (b) Dendrites in an aluminum alloy (x 50).
(From ASM Handbook, Vol. 9, Metallography and
Microstructure (1985), ASM International, Materials
Park, OH 44073-0002.)
27. 27
27
Example 8.3 SOLUTION
Figure 8.10, we can mark five equal units on the vertical
scale and 12 equal units on the horizontal scale.The slope is:
28. 28
28
A 4-in.-diameter aluminum bar solidifies to a depth of 0.5 in.
beneath the surface in 5 minutes. After 20 minutes, the bar
has solidified to a depth of 1.5 in. How much time is required
for the bar to solidify completely?
Example 8.4 SOLUTION
From our measurements, we can determine the constants
ksolidification and c1.
Example 8.4
Time of Solidification
32. 32
32
Recalescence - The increase in temperature of an
undercooled liquid metal as a result of the liberation of
heat during nucleation.
Thermal arrest - A plateau on the cooling curve during
the solidification of a material caused by the evolution of
the latent heat of fusion during solidification.
Total solidification time - The time required for the
casting to solidify completely after the casting has been
poured.
Local solidification time - The time required for a
particular location in a casting to solidify once nucleation
has begun.
Section 8.6 Cooling Curves
34. 34
34
Chill zone - A region of small, randomly oriented grains
that forms at the surface of a casting as a result of
heterogeneous nucleation.
Columnar zone - A region of elongated grains having a
preferred orientation that forms as a result of
competitive growth during the solidification of a casting.
Equiaxed zone - A region of randomly oriented grains in
the center of a casting produced as a result of
widespread nucleation.
Section 8.7 Cast Structure
37. 37
37
Shrinkage - Contraction of a casting during solidification.
Microshrinkage - Small, frequently isolated pores
between the dendrite arms formed by the shrinkage that
accompanies solidification.
Gas porosity - Bubbles of gas trapped within a casting
during solidification, caused by the lower solubility of the
gas in the solid compared with that in the liquid.
Sievert’s law - The amount of a gas that dissolves in a
metal is proportional to the partial pressure of the gas in
the surroundings.
Section 8.8 Solidification Defects
41. 41
41
Example 8.6 SOLUTION
We know that the riser must freeze after the casting. To
be conservative, however, we typically require that the
riser take 25% longer to solidify than the casting.
Therefore:
45. 45
45
After melting at atmospheric pressure, molten copper
contains 0.01 weight percent oxygen. To assure that your
castings will not be subject to gas porosity, you want to
reduce the weight percent to less than 0.00001% prior to
pouring. Design a degassing process for the copper.
Example 8.7
Design of a Degassing Process for Copper
46. 46
46
Example 8.7 SOLUTION
In one approach, the liquid copper is placed in a vacuum
chamber; the oxygen is then drawn from the liquid and
carried away into the vacuum. The vacuum required can
be estimated from Sievert’s law:
Another approach would be to introduce a copper-15%
phosphorous alloy. The phosphorous reacts with
oxygen to produce P2O5, which floats out of the liquid,
by the reaction:
5O + 2P P2O5
47. 47
47
Sand casting - A casting process using sand molds.
Investment casting - A casting process that is used for
making complex shapes such as turbine blades, also
known as the lost wax process.
Lost foam process - A process in which a polymer foam is
used as a pattern to produce a casting.
Permanent mold casting - A casting process in which a
mold can be used many times.
Pressure die casting - A casting process in which molten
metal/alloys is forced into a die under pressure.
Section 8.9 Casting Processes for
Manufacturing Components
49. 49
49
Figure 8-20 Engine block produced using the
lost foam casting process. (Courtesy of Paul
Arch, Nova Chemicals.)
50. 50
50
Ingot casting - The process of casting ingots.This is
different from the continuous casting route.
Continuous casting - A process to convert molten metal
or an alloy into a semi-finished product such as a slab.
Section 8.10 Continuous Casting
and Ingot Casting
51. 51
51
Figure 8.21 Summary of steps in the extraction of steels
using iron ores, coke and limestone. (Source:
www.steel.org. Used with permission of the American
Iron and Steel Institute.)
53. 53
53
Figure 8.23 Secondary processing steps in processing of steel
and alloys. (Source: www.steel.org. Used with permission of
the American Iron and Steel Institute.)
54. 54
54
Figure 8.24 shows a method for continuous casting of 0.25-
in.-thick, 48-in.-wide aluminum plate that is subsequently
rolled into aluminum foil. The liquid aluminum is introduced
between two large steel rolls that slowly turn. We want the
aluminum to be completely solidified by the rolls just as the
plate emerges from the machine. The rolls act as a permanent
mold with a mold constant B of about 5 min/in.2 when the
aluminum is poured at the proper superheat. Design the rolls
required for this process.
Example 8.8
Design of a Continuous Casting Machine
56. 56
56
Example 8.8 SOLUTION
The average thickness is (0.50 in. + 0.25 in.)/2 = 0.375
in. Then:
V = (thickness)(length)(width) = 0.375lw
A = 2(length)(width) = 2lw
V/A = (0.375lw)/(2lw) = 0.1875 in.
57. 57
57
In selecting our final design, we prefer to use the largest
practical roll diameter to assure high production rates. As
the rolls become more massive, however, they and their
supporting equipment become more expensive.
Example 8.8 SOLUTION (Continued)
58. 58
58
Directional solidification (DS) - A solidification technique
in which cooling in a given direction leads to preferential
growth of grains in the opposite direction, leading to an
anisotropic-oriented microstructure.
Bridgman processes - A process to grow semiconductor
and other single crystals.
Epitaxial growth - Growth of a material via epitaxy.
Homoepitaxy - Growth of a highly oriented material onto
a crystal of the same material.
Heteroepitaxy - Growth of a highly oriented material onto
a different substrate material.
Section 8.11 Directional
Solidification (DS), Single Crystal
Growth, and Epitaxial Growth
60. 60
60
Figure 8.26 (a) Silicon
single crystal, (b) silicon
wafer, and (c) Bridgman
technique. (Courtesy of
PhotoDisc/Getty Images.)
61. 61
61
Lamellar - A plate-like arrangement of crystals within a
material.
Spherulite - Spherical-shaped crystals produced when
certain polymers solidify.
Preform - A component from which a fiber is drawn or a
bottle is made.
Section 8.12 Solidification of
Polymers and Inorganic Glasses
62. 62
62
Figure 8.27 An amorphous
boundary region separates the
lamellae. A spherulite in
polystyrene (8000). (From R.
Young and P. Lovell, Introduction
to Polymers, 2nd Ed., Chapman &
Hall, 1991).
64. 64
64
Brazing - An alloy, known as a filler, is used to join two
materials to one another.
Soldering - Soldering is a joining process in which the
filler has a melting temperature below 450o
C, no
melting of the base materials occurs.
Fusion welding - Joining processes in which a portion of
the materials must melt in order to achieve good
bonding.
Fusion zone - The portion of a weld heated to produce
all liquid during the welding process. Solidification of the
fusion zone provides joining.
Section 8.13 Joining of Metallic
Materials