Eutectic Solidification
•Download as PPTX, PDF•
10 likes•8,920 views
The document discusses eutectic solidification, where a liquid transforms into two solid phases at a single temperature. It describes how one phase will form via diffusion in the liquid, depleting the local area of one constituent and pushing the composition into the solid phase range. This causes the second phase to form adjacent to the first. The two phases then grow side-by-side in a laminated microstructure. There are two types of eutectic solidification: normal, where the phases form alternate lamellae via diffusion between the phases; and anomalous, where one phase is capable of faceting and forms irregular microstructures sensitive to growth conditions.
Report
Share
Report
Share
Recommended
Solidification
The process of transformation of a substance from liquid to solid state in which the crystal lattice forms and crystals appear.
•Volume shrinkage or volume contraction
Solidification
This document discusses solidification processes and their effects on material properties. Rapid solidification using techniques like atomization and melt spinning allows materials to solidify too quickly for thermodynamic restrictions, exceeding solubility limits and forming non-equilibrium crystalline or amorphous phases without chemical changes. This results in microsegregation-free structures with improved mechanical properties compared to conventional solidification of ingots and castings, which causes non-uniform segregation of impurities and alloying elements that depends on cooling rates. Segregation forms bands and patterns within solidified materials that affect properties.
Metal casting ppt3
The document discusses various aspects of solidification processes for pure metals and alloys. It covers topics such as solidification curves, grain structure formation, mushy zone formation in alloys, segregation of elements, shrinkage during solidification, and directional solidification techniques. It also discusses the functions and design of gating systems, including elements like pouring basins, sprues, runners, gates, and risers.
Dendratic growth
- Dendritic crystal growth occurs when a liquid-solid interface moves into a supercooled liquid. Heat is removed from the interface into both the solid and liquid.
- Undercooling of the liquid allows the formation of spikes at the interface that grow faster than the surrounding interface. This leads to the formation of branched, tree-like dendritic structures.
- Secondary and tertiary branches can form from primary branches/spikes. The branching occurs due to temperature gradients that arise from the release of heat at the interface.
05 dislocation theory
The document discusses dislocation theory and behavior in different crystal structures. It covers:
- Observation techniques for dislocations like etching and transmission electron microscopy
- Key concepts like Burgers vector, dislocation loops, and dissociation of dislocations into partial dislocations
- Differences in dislocation behavior in FCC, BCC, and HCP lattices including slip systems and interactions between dislocations
- Stress fields and strain energies of dislocations as well as forces acting on dislocations and between dislocations
- Mechanisms of dislocation motion including glide, cross-slip, and climb that enable plastic deformation.
Lecture: Solidification and Growth Kinetics
Phase transformations in metals and alloys (Third Edition),
By: Porter, Easterling, and Sherif (CRC Press, 2009)
Steel Making: Ingot casting defects
1) The document discusses various defects that can occur during steel ingot solidification such as pipe, columnar structure, blow holes, and segregation.
2) It provides remedies for preventing these defects, such as using a hot top feeder head to avoid pipe formation and soaking ingots to minimize segregation.
3) The document also covers the mechanisms of ingot solidification, describing how killed, rimmed, and semi-killed steels solidify into chill, columnar, and equiaxed zones within the ingot.
Solidification of metals
This document discusses the solidification of metals. It begins with an introduction to metals and their importance in dentistry. It then covers the classification of metals and their properties like conductivity. The document discusses the history of metals and how solidification occurs through nucleation and crystal growth below the melting point. It provides examples of solidification patterns in metals like steel and how properties like carbon content affect the patterns.
Recommended
Solidification
The process of transformation of a substance from liquid to solid state in which the crystal lattice forms and crystals appear.
•Volume shrinkage or volume contraction
Solidification
This document discusses solidification processes and their effects on material properties. Rapid solidification using techniques like atomization and melt spinning allows materials to solidify too quickly for thermodynamic restrictions, exceeding solubility limits and forming non-equilibrium crystalline or amorphous phases without chemical changes. This results in microsegregation-free structures with improved mechanical properties compared to conventional solidification of ingots and castings, which causes non-uniform segregation of impurities and alloying elements that depends on cooling rates. Segregation forms bands and patterns within solidified materials that affect properties.
Metal casting ppt3
The document discusses various aspects of solidification processes for pure metals and alloys. It covers topics such as solidification curves, grain structure formation, mushy zone formation in alloys, segregation of elements, shrinkage during solidification, and directional solidification techniques. It also discusses the functions and design of gating systems, including elements like pouring basins, sprues, runners, gates, and risers.
Dendratic growth
- Dendritic crystal growth occurs when a liquid-solid interface moves into a supercooled liquid. Heat is removed from the interface into both the solid and liquid.
- Undercooling of the liquid allows the formation of spikes at the interface that grow faster than the surrounding interface. This leads to the formation of branched, tree-like dendritic structures.
- Secondary and tertiary branches can form from primary branches/spikes. The branching occurs due to temperature gradients that arise from the release of heat at the interface.
05 dislocation theory
The document discusses dislocation theory and behavior in different crystal structures. It covers:
- Observation techniques for dislocations like etching and transmission electron microscopy
- Key concepts like Burgers vector, dislocation loops, and dissociation of dislocations into partial dislocations
- Differences in dislocation behavior in FCC, BCC, and HCP lattices including slip systems and interactions between dislocations
- Stress fields and strain energies of dislocations as well as forces acting on dislocations and between dislocations
- Mechanisms of dislocation motion including glide, cross-slip, and climb that enable plastic deformation.
Lecture: Solidification and Growth Kinetics
Phase transformations in metals and alloys (Third Edition),
By: Porter, Easterling, and Sherif (CRC Press, 2009)
Steel Making: Ingot casting defects
1) The document discusses various defects that can occur during steel ingot solidification such as pipe, columnar structure, blow holes, and segregation.
2) It provides remedies for preventing these defects, such as using a hot top feeder head to avoid pipe formation and soaking ingots to minimize segregation.
3) The document also covers the mechanisms of ingot solidification, describing how killed, rimmed, and semi-killed steels solidify into chill, columnar, and equiaxed zones within the ingot.
Solidification of metals
This document discusses the solidification of metals. It begins with an introduction to metals and their importance in dentistry. It then covers the classification of metals and their properties like conductivity. The document discusses the history of metals and how solidification occurs through nucleation and crystal growth below the melting point. It provides examples of solidification patterns in metals like steel and how properties like carbon content affect the patterns.
Nucleation in Crystalline Structures
Nucleation in crystalline structures, homogeneous and heterogeneous nucleation, calculation of critical radius of nucleation
Solidification of alloys
solidification of alloys nucleation, crystellization and grain growth
dendritic growth iso morphous eutectic and peritectic solidification
Solidification of metals by Hari prasad
The document discusses solidification processes during casting and welding. It defines key terms like solidification, nucleation, homogeneous and heterogeneous nucleation. It explains the factors that affect solidification like Gibbs free energy, entropy, latent heat and undercooling. It differentiates between solidification in pure metals and alloys. It also describes the types of nucleation and grain growth during solidification as well as the formation of solid solutions.
ceramic sintering
The document discusses rate controlled sintering in advanced ceramic processes. It explains that sintering transforms ceramic powder compacts into dense materials through heating by reducing pores and growing grains. The driving force is lowering free energy. Sintering occurs in three stages and is affected by various factors. Rate controlled sintering controls the heating rate or temperature to control the sintering process for improved material properties. It provides examples demonstrating the effects of heating rate on microstructure.
Dendritic growth in pure metals
Dendritic crystalline growth occurs when a liquid-solid interface moves into supercooled liquid. Heat is removed from the interface into both the solid and liquid, creating a temperature inversion where the interface is hottest. Small perturbations in the interface can then grow into branched crystal structures called dendrites, as protrusions into cooler liquid regions will grow faster relatively. Secondary and even tertiary branches can then form on the primary branches through similar temperature gradient-driven processes, resulting in a tree-like crystalline structure.
VACUUM DE-GASING OF METALS
Vacuum de-gassing is a process to remove entrapped gases like hydrogen, nitrogen, and oxides from liquid metals. It works by creating a vacuum at the melt surface, which shifts dissolution equilibriums towards gas evolution and removal. Two main methods are vacuum degassing in a ladle and electric arc degassing, which can maintain vacuum longer for better cleaning. Vacuum degassing improves metal purity by removing gases and inclusions.
Recovery recrystallization grain_growth
The document discusses three microstructural transformations: recovery, recrystallization, and grain growth that occur during annealing of cold worked materials. Recovery involves a reduction in point defects and dislocation rearrangement into low energy configurations at low annealing temperatures. Recrystallization occurs at higher annealing temperatures and results in the formation of new strain-free grains. Grain growth follows recrystallization and leads to an increase in the average grain size as larger grains grow at the expense of smaller ones.
Twing Roll Casting
This document summarizes a study comparing the microstructure and properties of phosphor bronze strips produced using twin roll strip casting versus a conventional horizontal continuous casting (HCC) process. Strips produced with twin roll casting showed significantly less inverse tin segregation compared to HCC. Microstructure analysis found the twin roll cast strips had finer, more equiaxed grains due to rapid solidification and higher cooling rates. Differences in crystallographic texture were also observed between the two casting methods in the as-cast condition. The twin roll casting process was able to produce phosphor bronze strips with superior properties to conventional HCC.
Forms of corrosion
A presentation giving the classification of corrosion and various forms of corrosion. Basic features of these various forms re given.
L 04
Strengthening mechanisms in metals include work hardening, solid solution strengthening, and precipitation hardening. Work hardening increases yield strength by introducing dislocations through plastic deformation, which impede further dislocation movement. Solid solution strengthening adds solute atoms that distort the crystal lattice and interfere with dislocations. Precipitation hardening involves heat treating alloys to form precipitates that impede dislocations. These mechanisms strengthen metals by making dislocation motion and propagation more difficult.
Deoxidation and inclusion control
This document discusses the deoxidation of steel and inclusion control during steelmaking. It explains that oxygen dissolves in steel during production under oxidizing conditions and must be removed through deoxidation. Common deoxidizers like aluminum, silicon, and manganese are added as they have a high affinity for oxygen and form stable oxides. The thermodynamics and kinetics of the deoxidation reaction are described. Proper stirring of the melt is important to allow the deoxidation products to float to the surface and be removed. Calcium injection can also be used to modify inclusions and make them more globular and easier to remove from the steel.
Sintering
The document discusses the process of sintering, which involves heating powdered materials below their melting point to bond particles together through atomic diffusion. Sintering reduces porosity and improves material properties. It explains the stages of sintering - initial neck growth, intermediate pore channel closure, and final pore shrinkage. Different sintering mechanisms are described, including surface, grain boundary, and lattice diffusion. Solid-state, liquid-phase, and reactive sintering types are also summarized. Key sintering parameters and the advantages and disadvantages of the process are presented.
PLASTIC DEFORMATION
This document discusses plastic deformation in metals caused by the motion of dislocations. There are two main types of dislocations - edge and screw. Dislocations normally move under shear stress, allowing permanent deformation. Slip and twinning are two modes of plastic deformation that involve the motion of dislocations on specific crystallographic planes and directions. Strengthening methods like work hardening, solid solution strengthening, grain refinement, and precipitation hardening make it harder for dislocations to move by introducing barriers to their motion. This increases the strength of metals.
Powder metallurgy
Powder metallurgy is a process that involves compacting and forming metal powders into a solid object through sintering. It consists of 3 main steps - producing metal powders through various methods, compacting the powders into a green compact through pressing, and sintering the compact by heating it to fuse the particles together into a solid object. It allows for net-shape production of complex parts and close dimensional tolerances, and is used for applications where other fabrication methods are not suitable.
Weldability testings
The document discusses various weldability tests used to evaluate the suitability of materials for welding and the performance of welded joints. It describes tests such as the Murex test, Houldcroft test, ring weldability test, controlled thermal severity test, Tekken test, implant test, and Lehigh restraint test. These tests are employed to quantify weldability and provide clues on precautions needed like filler material selection, preheat, and energy input to minimize defects like hot cracking and cold cracking in welded joints.
Dendritic growth in pure metals
Dendritic crystal growth occurs when a liquid-solid interface moves into supercooled liquid. Heat is released at the interface, causing a temperature inversion where the interface is hotter than the surrounding liquid and solid. Small perturbations at the interface can then grow out into the liquid, forming branched crystal structures that resemble trees, hence the term "dendrite." Secondary and tertiary branches form on the primary branches as the temperature gradient causes further crystalline growth perpendicular to the initial branches.
Heat treatment, phases, microstructures and its properties
The document discusses phases, microstructures, and properties in materials. It defines a phase as a region that differs in structure and/or composition from another region. It explains that phase diagrams provide information on the number and types of phases present at different temperatures and compositions, and can show equilibrium solid solubility and temperature ranges for phase changes. Gibb's phase rule relates the number of phases, components, and degrees of freedom in a system. Solid solutions are discussed as single-phase atomic mixtures, including substitutional and interstitial types. The iron-carbon phase diagram is examined in detail, outlining the different phases such as austenite, ferrite, cementite, and eutectic or peritectic
Cvd
Chemical Vapour Deposition,types of cvd processes,Atomic layer cvd,Classification of cvd by reactor types,Theoretical concepts in cvd.
Powder Metallurgy - PROCESS
The document discusses the powder metallurgy process which consists of three main steps: 1) blending and mixing of metal powders and additives, 2) compaction of the blended powder using pressure-based or pressureless techniques, and 3) sintering the compacted powder below the melting point to bond the particles together without melting. Optional secondary operations such as heat treatment, machining or infiltration can further process the sintered parts.
Steel Making: Lecture deoxidation
The document discusses the process of deoxidizing steel. During steelmaking, oxygen dissolves into the liquid steel but not in the solid steel. Deoxidation or "killing" of steel refers to reducing the excess oxygen content before casting to prevent blowholes and inclusions. This is typically done through precipitation deoxidation using elements like aluminum, silicon, and manganese that have a higher affinity for oxygen than iron and form stable oxides. These deoxidizers are chosen based on factors like stability, deoxidizing ability, oxide melting point and density. Aluminum is the most powerful deoxidizer but its oxide alumina must be modified to remain liquid during casting.
Solidification of material
1. Solidification occurs when a liquid metal cools and transforms into a solid below its melting point, through the process of nucleation and crystal growth.
2. During nucleation, small clusters of atoms (nuclei) form in the undercooled liquid, which must reach a critical size to become stable crystals.
3. Once stable nuclei form, the crystals grow through addition of atoms from the liquid until they impinge on neighboring crystals. Cooling curves can be used to study phase changes during solidification of pure metals and alloys.
SOLIDIFICATION OF CASTING
This document discusses the process of solidification in castings. It covers topics including the introduction to solidification, concepts of solidification in castings, solidification of pure metals and alloys, nucleation and growth. Specifically, it describes how solidification begins with the formation of nuclei near the mold walls and progresses through dendritic growth until the entire melt is crystallized. It also discusses solidification curves and phase diagrams for pure metals and alloys.
More Related Content
What's hot
Nucleation in Crystalline Structures
Nucleation in crystalline structures, homogeneous and heterogeneous nucleation, calculation of critical radius of nucleation
Solidification of alloys
solidification of alloys nucleation, crystellization and grain growth
dendritic growth iso morphous eutectic and peritectic solidification
Solidification of metals by Hari prasad
The document discusses solidification processes during casting and welding. It defines key terms like solidification, nucleation, homogeneous and heterogeneous nucleation. It explains the factors that affect solidification like Gibbs free energy, entropy, latent heat and undercooling. It differentiates between solidification in pure metals and alloys. It also describes the types of nucleation and grain growth during solidification as well as the formation of solid solutions.
ceramic sintering
The document discusses rate controlled sintering in advanced ceramic processes. It explains that sintering transforms ceramic powder compacts into dense materials through heating by reducing pores and growing grains. The driving force is lowering free energy. Sintering occurs in three stages and is affected by various factors. Rate controlled sintering controls the heating rate or temperature to control the sintering process for improved material properties. It provides examples demonstrating the effects of heating rate on microstructure.
Dendritic growth in pure metals
Dendritic crystalline growth occurs when a liquid-solid interface moves into supercooled liquid. Heat is removed from the interface into both the solid and liquid, creating a temperature inversion where the interface is hottest. Small perturbations in the interface can then grow into branched crystal structures called dendrites, as protrusions into cooler liquid regions will grow faster relatively. Secondary and even tertiary branches can then form on the primary branches through similar temperature gradient-driven processes, resulting in a tree-like crystalline structure.
VACUUM DE-GASING OF METALS
Vacuum de-gassing is a process to remove entrapped gases like hydrogen, nitrogen, and oxides from liquid metals. It works by creating a vacuum at the melt surface, which shifts dissolution equilibriums towards gas evolution and removal. Two main methods are vacuum degassing in a ladle and electric arc degassing, which can maintain vacuum longer for better cleaning. Vacuum degassing improves metal purity by removing gases and inclusions.
Recovery recrystallization grain_growth
The document discusses three microstructural transformations: recovery, recrystallization, and grain growth that occur during annealing of cold worked materials. Recovery involves a reduction in point defects and dislocation rearrangement into low energy configurations at low annealing temperatures. Recrystallization occurs at higher annealing temperatures and results in the formation of new strain-free grains. Grain growth follows recrystallization and leads to an increase in the average grain size as larger grains grow at the expense of smaller ones.
Twing Roll Casting
This document summarizes a study comparing the microstructure and properties of phosphor bronze strips produced using twin roll strip casting versus a conventional horizontal continuous casting (HCC) process. Strips produced with twin roll casting showed significantly less inverse tin segregation compared to HCC. Microstructure analysis found the twin roll cast strips had finer, more equiaxed grains due to rapid solidification and higher cooling rates. Differences in crystallographic texture were also observed between the two casting methods in the as-cast condition. The twin roll casting process was able to produce phosphor bronze strips with superior properties to conventional HCC.
Forms of corrosion
A presentation giving the classification of corrosion and various forms of corrosion. Basic features of these various forms re given.
L 04
Strengthening mechanisms in metals include work hardening, solid solution strengthening, and precipitation hardening. Work hardening increases yield strength by introducing dislocations through plastic deformation, which impede further dislocation movement. Solid solution strengthening adds solute atoms that distort the crystal lattice and interfere with dislocations. Precipitation hardening involves heat treating alloys to form precipitates that impede dislocations. These mechanisms strengthen metals by making dislocation motion and propagation more difficult.
Deoxidation and inclusion control
This document discusses the deoxidation of steel and inclusion control during steelmaking. It explains that oxygen dissolves in steel during production under oxidizing conditions and must be removed through deoxidation. Common deoxidizers like aluminum, silicon, and manganese are added as they have a high affinity for oxygen and form stable oxides. The thermodynamics and kinetics of the deoxidation reaction are described. Proper stirring of the melt is important to allow the deoxidation products to float to the surface and be removed. Calcium injection can also be used to modify inclusions and make them more globular and easier to remove from the steel.
Sintering
The document discusses the process of sintering, which involves heating powdered materials below their melting point to bond particles together through atomic diffusion. Sintering reduces porosity and improves material properties. It explains the stages of sintering - initial neck growth, intermediate pore channel closure, and final pore shrinkage. Different sintering mechanisms are described, including surface, grain boundary, and lattice diffusion. Solid-state, liquid-phase, and reactive sintering types are also summarized. Key sintering parameters and the advantages and disadvantages of the process are presented.
PLASTIC DEFORMATION
This document discusses plastic deformation in metals caused by the motion of dislocations. There are two main types of dislocations - edge and screw. Dislocations normally move under shear stress, allowing permanent deformation. Slip and twinning are two modes of plastic deformation that involve the motion of dislocations on specific crystallographic planes and directions. Strengthening methods like work hardening, solid solution strengthening, grain refinement, and precipitation hardening make it harder for dislocations to move by introducing barriers to their motion. This increases the strength of metals.
Powder metallurgy
Powder metallurgy is a process that involves compacting and forming metal powders into a solid object through sintering. It consists of 3 main steps - producing metal powders through various methods, compacting the powders into a green compact through pressing, and sintering the compact by heating it to fuse the particles together into a solid object. It allows for net-shape production of complex parts and close dimensional tolerances, and is used for applications where other fabrication methods are not suitable.
Weldability testings
The document discusses various weldability tests used to evaluate the suitability of materials for welding and the performance of welded joints. It describes tests such as the Murex test, Houldcroft test, ring weldability test, controlled thermal severity test, Tekken test, implant test, and Lehigh restraint test. These tests are employed to quantify weldability and provide clues on precautions needed like filler material selection, preheat, and energy input to minimize defects like hot cracking and cold cracking in welded joints.
Dendritic growth in pure metals
Dendritic crystal growth occurs when a liquid-solid interface moves into supercooled liquid. Heat is released at the interface, causing a temperature inversion where the interface is hotter than the surrounding liquid and solid. Small perturbations at the interface can then grow out into the liquid, forming branched crystal structures that resemble trees, hence the term "dendrite." Secondary and tertiary branches form on the primary branches as the temperature gradient causes further crystalline growth perpendicular to the initial branches.
Heat treatment, phases, microstructures and its properties
The document discusses phases, microstructures, and properties in materials. It defines a phase as a region that differs in structure and/or composition from another region. It explains that phase diagrams provide information on the number and types of phases present at different temperatures and compositions, and can show equilibrium solid solubility and temperature ranges for phase changes. Gibb's phase rule relates the number of phases, components, and degrees of freedom in a system. Solid solutions are discussed as single-phase atomic mixtures, including substitutional and interstitial types. The iron-carbon phase diagram is examined in detail, outlining the different phases such as austenite, ferrite, cementite, and eutectic or peritectic
Cvd
Chemical Vapour Deposition,types of cvd processes,Atomic layer cvd,Classification of cvd by reactor types,Theoretical concepts in cvd.
Powder Metallurgy - PROCESS
The document discusses the powder metallurgy process which consists of three main steps: 1) blending and mixing of metal powders and additives, 2) compaction of the blended powder using pressure-based or pressureless techniques, and 3) sintering the compacted powder below the melting point to bond the particles together without melting. Optional secondary operations such as heat treatment, machining or infiltration can further process the sintered parts.
Steel Making: Lecture deoxidation
The document discusses the process of deoxidizing steel. During steelmaking, oxygen dissolves into the liquid steel but not in the solid steel. Deoxidation or "killing" of steel refers to reducing the excess oxygen content before casting to prevent blowholes and inclusions. This is typically done through precipitation deoxidation using elements like aluminum, silicon, and manganese that have a higher affinity for oxygen than iron and form stable oxides. These deoxidizers are chosen based on factors like stability, deoxidizing ability, oxide melting point and density. Aluminum is the most powerful deoxidizer but its oxide alumina must be modified to remain liquid during casting.
What's hot (20)
Heat treatment, phases, microstructures and its properties
Heat treatment, phases, microstructures and its properties
Viewers also liked
Solidification of material
1. Solidification occurs when a liquid metal cools and transforms into a solid below its melting point, through the process of nucleation and crystal growth.
2. During nucleation, small clusters of atoms (nuclei) form in the undercooled liquid, which must reach a critical size to become stable crystals.
3. Once stable nuclei form, the crystals grow through addition of atoms from the liquid until they impinge on neighboring crystals. Cooling curves can be used to study phase changes during solidification of pure metals and alloys.
SOLIDIFICATION OF CASTING
This document discusses the process of solidification in castings. It covers topics including the introduction to solidification, concepts of solidification in castings, solidification of pure metals and alloys, nucleation and growth. Specifically, it describes how solidification begins with the formation of nuclei near the mold walls and progresses through dendritic growth until the entire melt is crystallized. It also discusses solidification curves and phase diagrams for pure metals and alloys.
Cooling curve
Cooling curves plot the temperature changes that occur as a material cools over its entire temperature range. For pure metals, the cooling curve shows a horizontal line at the freezing/melting temperature. For alloys, cooling curves are used to determine initial and final phase change temperatures, which are then used to construct phase diagrams. Different alloy compositions produce different cooling curve shapes, allowing identification of pure metals, solid solutions, and eutectic compositions.
Castanal1
This document provides an overview of the melting and pouring processes in casting. It discusses the key steps - melting, pouring, solidification and cooling. It then examines the melting process in more detail, covering furnace design, heat transfer calculations for melting, and examples calculations for melting time. The document also analyzes fluid flow during pouring using concepts like Reynolds number, Bernoulli's equation and continuity. It provides examples of calculating pouring velocities and mold filling times. Finally, it discusses bottom gated casting systems and examples of calculating filling times for such systems.
Solidification of metals
This document discusses the properties of liquid and solid phases of metals. It notes that while solids and gases can be easily classified, liquids have many unknown properties. X-ray diffraction has shown that liquids have short-lived ordered atomic structures similar to solids. There is only a small difference in bonding between solids and liquids. The document also examines how the free energy of solids, liquids, and gases varies with temperature and pressure, and discusses the melting point, boiling point, and triple point of phase changes.
Solidification & Melting Process
The document discusses solidification and casting processes. It describes how solidification occurs through nucleation and growth, and the factors that influence these processes like undercooling. It also discusses different types of nucleation and how interfacial energies affect nucleation barriers. Furnace selection factors for melting metals are outlined, including common furnace types like cupolas and their design and operation principles. The advantages and limitations of cupola furnaces are summarized.
Fusion 360 learning guide v1
If you're looking to learn Fusion 360 or just looking to learn a little more about a certain environment in the program, this one page guide should help you out. Videos, forum posts and tutorials all brought together in one sheet to help you quickly learn the software and see those things most important to you.
Solidification and microstructure of metals
The document discusses the properties and uses of metals in dentistry. It defines metals and describes their classification into ferrous and non-ferrous groups. Metals solidify through the formation of crystal nuclei that grow into dendritic structures within grains. Smaller grain size improves properties. Dental alloys like cobalt-chromium, titanium, and nickel-chromium are used for implants, crowns, and dentures due to their strength, corrosion resistance, and biocompatibility. Precious metals are also used for restorations.
Diffusion report
The document is a 23-page PowerPoint presentation about diffusion in materials science. It covers topics like the definition of diffusion, different types of diffusion like interdiffusion and self-diffusion, diffusion mechanisms like vacancy and interstitial diffusion, mathematics of diffusion using Fick's laws of steady-state and non-steady-state diffusion, examples calculations, and factors that affect diffusion rates such as temperature, microstructure, and the diffusing species. The presentation provides an overview of key concepts and equations regarding diffusion for a materials science class.
Microstructures
The document discusses microstructures in steels and other alloys. It includes images and descriptions of different microstructures like pearlite, martensite, bainite, and ferrite that form under various cooling conditions from austenite. It also discusses microstructures in cast irons like spheroidal graphite, flake graphite, and ledeburite. The final section discusses sealed quench furnaces and includes images of loads of components prepared for case hardening and quenching treatments.
Nucleation & crystallization
The document discusses nucleation and crystallization processes. It explains that nucleation refers to the initial formation of nano-sized crystallites from molten material as the first step in solidification. The critical radius is the minimum size needed for a crystal embryo to become a stable nucleus and continue growing. Segregation occurs as solute elements are more soluble in liquid than solid, causing compositional variations within castings.
Study of Plain Carbon Steel
This document discusses plain carbon steel, which is an iron alloy containing a maximum of 1.5% carbon. It classifies plain carbon steels as low carbon (<0.25% C), medium carbon (0.3-0.6% C), or high carbon (0.6-2% C). Low carbon steel has good ductility but low strength, while high carbon steel has high strength but low ductility. Common impurities like silicon, manganese, sulfur, and phosphorus affect the properties. The document describes the microstructure and applications of each type of plain carbon steel.
2006 E.C. aait materials i regular chapter 6 introduction to phase diagrams
this is an engineering material one lecture slides on chapter five on phase diagram from ins. getasew tadesse in the 2014/2015 acadamic calander.
Phase transitions
Phase transitions can be classified based on their order, mechanism, and thermodynamics. First order transitions involve a discontinuity in the first derivative of Gibbs free energy. Second order transitions have a continuous first derivative but discontinuity in the second derivative. Reconstructive transitions involve major structure reorganization while displacive transitions involve bond distortion. The kinetics of phase transitions involve nucleation and growth. Martensitic transformations occur via shear without diffusion. The BaTiO3 transition from cubic to tetragonal structure results in it becoming ferroelectric below 120°C. Glass transitions occur when liquids are cooled too fast to crystallize, becoming supercooled liquids called glasses.
Phase Diagram
This document provides an introduction to phase diagrams and phase equilibria. It defines key terms like system, phase, variables, components, alloys, and solid solutions. It describes Gibbs phase rule and how it relates the number of phases, components, and degrees of freedom in a system. It explains Gibbs free energy and how it indicates the thermodynamic stability of phases. It also discusses cooling curves for pure metals, binary solid solutions, eutectic alloys, and off-eutectic alloys. Hume-Rothery rules for solid solubility and interpreting phase diagrams are also summarized.
6 phase and phase equilibrium chapter
•Introduction - Components – Phase
•Phases – Solution
•Solid solutions
•Intermediate Alloy Phases
•Non-homogenous Phases / Mechanical Mixtures
•Hume Rothery Rule’s for Solid Solution
•Solidification
•Equilibrium Phase Diagram - Unary
•Cooling Curves
•Binary phase diagram
•Lever Arm Principle
•Gibbs’s Phase Rule
•Reactions in binary phase diagrams
Diffusion in Materials
This document discusses the process of diffusion in materials. It defines diffusion as the movement of atoms within a material driven by concentration gradients. There are four main mechanisms of diffusion: self-diffusion, interchange diffusion, vacancy diffusion, and interstitial diffusion. Diffusion is thermally activated and follows the Arrhenius equation, requiring atoms to overcome an activation energy barrier. Fick's first law describes the flux of atoms down a concentration gradient, while Fick's second law models the change in concentration over time. Diffusion plays a key role in processes like grain growth, diffusion bonding, and sintering of materials.
iron-iron carbide Phase diagrams
This document provides an overview of phase diagrams and key concepts related to phase diagrams, including:
- Common components of phase diagrams like phases, solubility limits, and microstructure.
- How to interpret phase diagrams to determine phases present, phase compositions, and relative amounts.
- Common reactions shown on phase diagrams like eutectic, eutectoid, and peritectic reactions.
- Examples of specific binary alloy phase diagrams like Cu-Ni, Pb-Sn, Al-Si, and Fe-Fe3C.
- How to use phase diagrams to understand alloy microstructure and properties.
Metallurgy basics (Iron phase diagram)
This document summarizes Piyush Verma's presentation on the Fe-Fe3C phase diagram for plain carbon steel. It introduces the key phases in iron like ferrite, austenite, cementite and pearlite. It explains how carbon enters the iron crystal lattice and affects its properties. The phase diagram shows the different phases present at various temperatures and carbon concentrations. It also describes the mechanisms of phase transformations like reconstructive and displacive transformations during heating and cooling of steel.
Chapter 9 phase diagrams 1
The document provides information on phase diagrams, including definitions of key concepts like phases, phase equilibria, and binary phase diagrams. It discusses one-component and binary systems, focusing on isomorphous, eutectic, and iron-carbon systems. For binary systems, it explains how to interpret phase diagrams to determine the phases present, phase compositions, and phase amounts using rules like lever rule. It summarizes common reactions like eutectic, eutectoid, and peritectic and analyzes the iron-carbon phase diagram in detail.
Viewers also liked (20)
2006 E.C. aait materials i regular chapter 6 introduction to phase diagrams
2006 E.C. aait materials i regular chapter 6 introduction to phase diagrams
Similar to Eutectic Solidification
Lec Week 9 Phase diagrams(1).pptx
This document is about phases and phase diagram's interpretation. It includes information regarding compositional quantity, each phase quantity, overall composition, etc. It also tells about how to read a phasor diagram along with information regarding various components of these kinds of diagrams.
9 - Phase diagrams.pdf
Phase diagrams provide information about the equilibrium conditions and transformations between different phases in a material system. They describe how the phases of a material vary with changes in temperature, pressure, and composition.
This document discusses key concepts related to phase diagrams including phases, the Gibbs phase rule, one-component and binary phase diagrams, eutectic and peritectic reactions, intermediate phases, ternary diagrams, and lever rule. It provides examples of phase diagrams for common material systems like water, Cu-Ni, Pb-Sn, Mg-Pb, and Cu-Zn. Cooling curves are also explained to illustrate phase transformations.
mse-260-lecture-5.pdf
This document discusses three-phase reactions in phase diagrams and the development of microstructures in eutectic alloys. It describes the five most common three-phase reactions - eutectic, peritectic, monotectic, eutectoid, and peritectoid - and how they appear on phase diagrams. For eutectic alloys, it explains how the microstructure depends on the alloy composition relative to the eutectic composition, resulting in either a lamellar eutectic structure, primary solid plus eutectic, or primary solid plus eutectic. The strength of eutectic alloys can be increased by reducing the interlamellar spacing
10[1].Phase Diagrams.ppt
1. The document discusses phase diagrams and microstructures in alloys. It defines phases, phase diagrams, and key features of phase diagrams including binary systems.
2. Binary systems can have complete solubility between components, forming a single phase, or limited solubility, forming two phases. Phase diagrams map the equilibrium phases present at different temperatures and compositions.
3. Microstructures depend on cooling rate - equilibrium cooling allows phases to adjust to changing conditions while fast cooling "locks in" non-equilibrium structures with compositional variations. Eutectic systems form layered structures when cooled through the eutectic point.
Liquid Liquid Extraction
This PPT contains Basics and Detail study of Liquid Liquid Extraction.....one of the unit operation in Mass Transfer. Also contains solvent selection criteria.
Electrodes and potentiometry
1) Potentiometry uses electrodes to measure voltages that provide chemical information about analytes. The cell voltage indicates the activity of an unknown species if the activities of other species are known.
2) Reference electrodes maintain a fixed potential through a known composition. Indicator electrodes respond to analytes that can donate or accept electrons at the electrode.
3) When measuring potentiometrically, a reference electrode and indicator electrode are connected by a salt bridge. The cell voltage is measured as the difference between the electrodes' potentials and used to determine the unknown concentration through an equation.
NH Phase Diagrams.ppt
Phase diagrams provide information about the equilibrium phases that exist at different temperatures and compositions for a system. They show the phase transformations that can be expected when temperature or composition is changed. For a binary system, the phase diagram indicates whether single or multiple phases exist at different temperatures and compositions using lines to represent phase boundaries. The lever rule can be used to determine the fractions of each phase in a two-phase region of the diagram by calculating the ratio of distances on a tie line between the overall composition and phase boundaries.
Giant LO oscillation in the Zn1yxBex(Se,Te) multi-phonons percolative alloys
This document discusses Raman scattering experiments on ZnBe(Se,Te) alloys. It finds that within the percolation regime of 0.19<x<0.81:
1) The low-frequency LO component is overdamped.
2) The high-frequency LO component exhibits a red asymmetry and apparent blue shift compared to predictions.
3) These anomalies can be explained by a discrete multi-mode description for the low- and high-frequency components, where coupling between modes via the macroscopic polarization field results in a transfer of oscillator strength building a "giant" LO oscillation.
Zeta potential.pptx
It is the electrokinetic potential in colloidal dispersions.
Zeta potential is the potential difference between the dispersion medium and the stationary layer of fluid attached to the dispersed particle.
When a colloidal suspension is placed in an electrical field, the colloidal particles move in one direction (toward the positive pole).
The counter ions move is another direction (toward the negative pole).
The electric potential developed at the solid liquid interface is called Zeta (ζ )potential.
Zeta potential is not equal to surface potential.
Zeta potential is less than electro chemical potential.
Increasing the concentration of electrolytes in the solution results in the decrease in thickness of double layer.
Thickness is also influenced by increasing valency of ions.
Isoelectric point:
At this point electrolyte concentration is maximum, thickness of double layer becomes neligible . Particle replusive force minimum. Zeta potential is equal to zero.
1.5 elimination reaction
This power point presentation summarizes elimination reactions, specifically 1,2 elimination reactions. It defines elimination reactions as reactions where two atoms or groups are removed from a reactant to form an unsaturated product. 1,2 elimination reactions eliminate atoms or groups from the 1 and 2 positions on a molecule. Three possible mechanisms are discussed: E2, E1, and E1cb. Evidence for the E2 mechanism includes kinetic isotope effects, the element effect showing dependence on leaving group ability, and the lack of hydrogen exchange. The Saytzeff rule and factors influencing its application, like stability and transition state crowding, are also covered.
Octahedral Substitution reaction way.ppt
1. The document discusses mechanisms of substitution reactions in coordination compounds, including dissociative, associative, and interchange mechanisms. It provides details on the steps and intermediates involved in each.
2. Factors that affect the rates of substitution reactions are also examined, such as temperature, pressure, ionic strength, and solvent. The relationships between these factors and reaction rates are defined.
3. Dissociative and associative mechanisms are described for the replacement of coordinated water by other ligands in octahedral metal complexes. Evidence suggests dissociative (SN1-like) processes are often involved when the rate depends only on the metal complex concentration.
Effect of Solvent in UV-by M.Qasim.pptx
Uv/Vis absorption spectra can be affected by solvents. Polar solvents can cause spectral shifts in absorption maximum wavelength (solvatochromism) through intermolecular interactions. For π-π* transitions, more polar solvents often result in red shifts (bathochromism) as the excited state is stabilized more than the ground state. For n-π* transitions, polar solvents sometimes cause blue shifts (hypsochromism) as the ground state is stabilized more by hydrogen bonding. The extent of shifting depends on whether the chromophore participates in intramolecular or intermolecular hydrogen bonding. Conjugated systems experience less spectral shifting from solvents than systems with keto groups.
Similar to Eutectic Solidification (12)
Giant LO oscillation in the Zn1yxBex(Se,Te) multi-phonons percolative alloys
Giant LO oscillation in the Zn1yxBex(Se,Te) multi-phonons percolative alloys
Recently uploaded
Pollock and Snow "DEIA in the Scholarly Landscape, Session One: Setting Expec...
Pollock and Snow "DEIA in the Scholarly Landscape, Session One: Setting Expec...National Information Standards Organization (NISO)
This presentation was provided by Steph Pollock of The American Psychological Association’s Journals Program, and Damita Snow, of The American Society of Civil Engineers (ASCE), for the initial session of NISO's 2024 Training Series "DEIA in the Scholarly Landscape." Session One: 'Setting Expectations: a DEIA Primer,' was held June 6, 2024.The Diamonds of 2023-2024 in the IGRA collection
A review of the growth of the Israel Genealogy Research Association Database Collection for the last 12 months. Our collection is now passed the 3 million mark and still growing. See which archives have contributed the most. See the different types of records we have, and which years have had records added. You can also see what we have for the future.
How to Add Chatter in the odoo 17 ERP Module
In Odoo, the chatter is like a chat tool that helps you work together on records. You can leave notes and track things, making it easier to talk with your team and partners. Inside chatter, all communication history, activity, and changes will be displayed.
How to Make a Field Mandatory in Odoo 17
In Odoo, making a field required can be done through both Python code and XML views. When you set the required attribute to True in Python code, it makes the field required across all views where it's used. Conversely, when you set the required attribute in XML views, it makes the field required only in the context of that particular view.
PCOS corelations and management through Ayurveda.
This presentation includes basic of PCOS their pathology and treatment and also Ayurveda correlation of PCOS and Ayurvedic line of treatment mentioned in classics.
Pengantar Penggunaan Flutter - Dart programming language1.pptx
Pengantar Penggunaan Flutter - Dart programming language1.pptx
Exploiting Artificial Intelligence for Empowering Researchers and Faculty, In...
Exploiting Artificial Intelligence for Empowering Researchers and Faculty, In...Dr. Vinod Kumar Kanvaria
Exploiting Artificial Intelligence for Empowering Researchers and Faculty,
International FDP on Fundamentals of Research in Social Sciences
at Integral University, Lucknow, 06.06.2024
By Dr. Vinod Kumar KanvariaHow to Create a More Engaging and Human Online Learning Experience
How to Create a More Engaging and Human Online Learning Experience Wahiba Chair Training & Consulting
Wahiba Chair's Talk at the 2024 Learning Ideas Conference. How to Build a Module in Odoo 17 Using the Scaffold Method
Odoo provides an option for creating a module by using a single line command. By using this command the user can make a whole structure of a module. It is very easy for a beginner to make a module. There is no need to make each file manually. This slide will show how to create a module using the scaffold method.
Chapter 4 - Islamic Financial Institutions in Malaysia.pptx
Chapter 4 - Islamic Financial Institutions in Malaysia.pptxMohd Adib Abd Muin, Senior Lecturer at Universiti Utara Malaysia
This slide is special for master students (MIBS & MIFB) in UUM. Also useful for readers who are interested in the topic of contemporary Islamic banking.
Chapter wise All Notes of First year Basic Civil Engineering.pptx
Chapter wise All Notes of First year Basic Civil Engineering
Syllabus
Chapter-1
Introduction to objective, scope and outcome the subject
Chapter 2
Introduction: Scope and Specialization of Civil Engineering, Role of civil Engineer in Society, Impact of infrastructural development on economy of country.
Chapter 3
Surveying: Object Principles & Types of Surveying; Site Plans, Plans & Maps; Scales & Unit of different Measurements.
Linear Measurements: Instruments used. Linear Measurement by Tape, Ranging out Survey Lines and overcoming Obstructions; Measurements on sloping ground; Tape corrections, conventional symbols. Angular Measurements: Instruments used; Introduction to Compass Surveying, Bearings and Longitude & Latitude of a Line, Introduction to total station.
Levelling: Instrument used Object of levelling, Methods of levelling in brief, and Contour maps.
Chapter 4
Buildings: Selection of site for Buildings, Layout of Building Plan, Types of buildings, Plinth area, carpet area, floor space index, Introduction to building byelaws, concept of sun light & ventilation. Components of Buildings & their functions, Basic concept of R.C.C., Introduction to types of foundation
Chapter 5
Transportation: Introduction to Transportation Engineering; Traffic and Road Safety: Types and Characteristics of Various Modes of Transportation; Various Road Traffic Signs, Causes of Accidents and Road Safety Measures.
Chapter 6
Environmental Engineering: Environmental Pollution, Environmental Acts and Regulations, Functional Concepts of Ecology, Basics of Species, Biodiversity, Ecosystem, Hydrological Cycle; Chemical Cycles: Carbon, Nitrogen & Phosphorus; Energy Flow in Ecosystems.
Water Pollution: Water Quality standards, Introduction to Treatment & Disposal of Waste Water. Reuse and Saving of Water, Rain Water Harvesting. Solid Waste Management: Classification of Solid Waste, Collection, Transportation and Disposal of Solid. Recycling of Solid Waste: Energy Recovery, Sanitary Landfill, On-Site Sanitation. Air & Noise Pollution: Primary and Secondary air pollutants, Harmful effects of Air Pollution, Control of Air Pollution. . Noise Pollution Harmful Effects of noise pollution, control of noise pollution, Global warming & Climate Change, Ozone depletion, Greenhouse effect
Text Books:
1. Palancharmy, Basic Civil Engineering, McGraw Hill publishers.
2. Satheesh Gopi, Basic Civil Engineering, Pearson Publishers.
3. Ketki Rangwala Dalal, Essentials of Civil Engineering, Charotar Publishing House.
4. BCP, Surveying volume 1
ANATOMY AND BIOMECHANICS OF HIP JOINT.pdf
it describes the bony anatomy including the femoral head , acetabulum, labrum . also discusses the capsule , ligaments . muscle that act on the hip joint and the range of motion are outlined. factors affecting hip joint stability and weight transmission through the joint are summarized.
How to Manage Your Lost Opportunities in Odoo 17 CRM
Odoo 17 CRM allows us to track why we lose sales opportunities with "Lost Reasons." This helps analyze our sales process and identify areas for improvement. Here's how to configure lost reasons in Odoo 17 CRM
How to Fix the Import Error in the Odoo 17
An import error occurs when a program fails to import a module or library, disrupting its execution. In languages like Python, this issue arises when the specified module cannot be found or accessed, hindering the program's functionality. Resolving import errors is crucial for maintaining smooth software operation and uninterrupted development processes.
Advanced Java[Extra Concepts, Not Difficult].docx
This is part 2 of my Java Learning Journey. This contains Hashing, ArrayList, LinkedList, Date and Time Classes, Calendar Class and more.
How to Setup Warehouse & Location in Odoo 17 Inventory
In this slide, we'll explore how to set up warehouses and locations in Odoo 17 Inventory. This will help us manage our stock effectively, track inventory levels, and streamline warehouse operations.
বাংলাদেশ অর্থনৈতিক সমীক্ষা (Economic Review) ২০২৪ UJS App.pdf
বাংলাদেশের অর্থনৈতিক সমীক্ষা ২০২৪ [Bangladesh Economic Review 2024 Bangla.pdf] কম্পিউটার , ট্যাব ও স্মার্ট ফোন ভার্সন সহ সম্পূর্ণ বাংলা ই-বুক বা pdf বই " সুচিপত্র ...বুকমার্ক মেনু 🔖 ও হাইপার লিংক মেনু 📝👆 যুক্ত ..
আমাদের সবার জন্য খুব খুব গুরুত্বপূর্ণ একটি বই ..বিসিএস, ব্যাংক, ইউনিভার্সিটি ভর্তি ও যে কোন প্রতিযোগিতা মূলক পরীক্ষার জন্য এর খুব ইম্পরট্যান্ট একটি বিষয় ...তাছাড়া বাংলাদেশের সাম্প্রতিক যে কোন ডাটা বা তথ্য এই বইতে পাবেন ...
তাই একজন নাগরিক হিসাবে এই তথ্য গুলো আপনার জানা প্রয়োজন ...।
বিসিএস ও ব্যাংক এর লিখিত পরীক্ষা ...+এছাড়া মাধ্যমিক ও উচ্চমাধ্যমিকের স্টুডেন্টদের জন্য অনেক কাজে আসবে ...
Recently uploaded (20)
Pollock and Snow "DEIA in the Scholarly Landscape, Session One: Setting Expec...
Pollock and Snow "DEIA in the Scholarly Landscape, Session One: Setting Expec...
Pengantar Penggunaan Flutter - Dart programming language1.pptx
Pengantar Penggunaan Flutter - Dart programming language1.pptx
Exploiting Artificial Intelligence for Empowering Researchers and Faculty, In...
Exploiting Artificial Intelligence for Empowering Researchers and Faculty, In...
Digital Artefact 1 - Tiny Home Environmental Design
Digital Artefact 1 - Tiny Home Environmental Design
How to Create a More Engaging and Human Online Learning Experience
How to Create a More Engaging and Human Online Learning Experience
How to Build a Module in Odoo 17 Using the Scaffold Method
How to Build a Module in Odoo 17 Using the Scaffold Method
Chapter 4 - Islamic Financial Institutions in Malaysia.pptx
Chapter 4 - Islamic Financial Institutions in Malaysia.pptx
Chapter wise All Notes of First year Basic Civil Engineering.pptx
Chapter wise All Notes of First year Basic Civil Engineering.pptx
How to Manage Your Lost Opportunities in Odoo 17 CRM
How to Manage Your Lost Opportunities in Odoo 17 CRM
How to Setup Warehouse & Location in Odoo 17 Inventory
How to Setup Warehouse & Location in Odoo 17 Inventory
বাংলাদেশ অর্থনৈতিক সমীক্ষা (Economic Review) ২০২৪ UJS App.pdf
বাংলাদেশ অর্থনৈতিক সমীক্ষা (Economic Review) ২০২৪ UJS App.pdf
Eutectic Solidification
- 2. Lα+ β In eutectic reaction : liquid transforms into to two solid phases. Eutectic reaction
- 3. Eutectic composition liquid Liquid, L + L + L + Eutectic temperature Eutectic composition
- 4. Crystal of one phase forms (via diffusion in the liquid) Local area becomes “depleted” of one constituent. The depleted area near the solidification pushes the local composition into a solid forming range on the phase diagram. This causes the second solid phase to form adjacent to the first phase. Eutectic reaction Liquid, L + L + L + Eutectic Reaction (at eutectic temperature and composition)
- 5. Second solid phase forms Local area becomes Depleted in the second phase constituent Eutectic reaction Liquid, L + L + L +
- 6. The 2 phases grow side-by-side creating a laminated microstructure Eutectic reaction Liquid, L + L + L +
- 7. Eutectic reaction: Characteristic microstructure: laminates of each of the 2 phases Eutectic reaction Liquid, L + L + L +
- 8. Types of Eutectic solidification: 1.Normal 2.Anomalous Normal: • The two phases appear either as alternate lamellae or as rods of minor phase embedded in the other phase. • Involves two non-faceting phases. • This occurs when both phases have low entropy of fusion. • E.g.: Pb-Sn
- 9. The dark layers are Pb-rich α phase, the light layers are the Sn-rich β phase.
- 10. Anomalous: • This occurs when one component is capable of faceting i.e. has a high entropy of melting. • The phases appear as broken lamellar/irregular/complex regular or quasi regular. • Sensitive to solidification conditions and impurities and displace the much wider range of microstructures. • Non isothermal growth • E.g.: Al-Si alloy
- 11. Al-Si alloy
- 13. Growth Mechanism Cooperative growth: the two phases of the eutectic grow together as a diffusion couple. Divorced growth: the two phases of the eutectic grow separately. There is no direct exchange of solute between the two solid phases and no trijunction.
- 16. • As the A-rich α phase solidifies excess B diffuses a short distance laterally where it is incorporated in the B-rich α phase. Similarly the A atoms rejected ahead of the β diffuse to the tips of the adjacent α lamellae. • Rate of growth depends on rate of diffusion which in turn depends on interlamellar spacing λ. As λ increases rate of diffusion decreases and thus rate of growth of lamellae decreases. Figure 1. Growth of lamellar eutectics
- 17. Limit to λ Figure 2. Figure 3. Figure 4.
- 18. Calculation of λ* and growth rate Figure 5.
- 19. Calculation of λ* and growth rate Figure 6.
- 20. Tri-dependence of ΔT0, λ and v This equation shows that by varying the interface undercooling (ΔT0) it is possible to vary the growth rate (v) and spacing (λ) independently. It is therefore impossible to predict the spacing that will be observed for a given growth rate. However, controlled growth experiments show that a specific value of λ is always associated with a given growth rate.
- 21. Thank you