This document summarizes a study on the damping force characteristics of a granular damper with separated dual chambers and a single linear motion rod. Numerical simulations using the discrete element method were performed to investigate how the installation angle of the damper affects damping force when one chamber or both chambers are filled with elastomer particles.
The study found that when only one chamber is filled, making the installation angle closer to vertical causes the particles to gather at the bottom due to gravity, restricting their movement and increasing damping force. However, when both chambers are filled, the damping forces from compressing particles in each chamber cancel out, so installation angle has little effect on damping force.
This document summarizes an experimental study and numerical simulation of a single-rod damper that uses an elastomer particle assemblage instead of oil. The study investigated the damper force characteristics of a prototype dual-chamber single-rod damper with elastomer particles in one chamber. Experiments varied the packing ratio of particles, vibration frequency, particle material properties, and stroke center position. A numerical simulation using the discrete element method modeled particle behavior inside the damper and agreed with experimental results, showing large hysteresis in damper force due to particle deformation.
1. Hooke's law states that the stress and strain of a material are proportional for small deformations.
2. Young's modulus is a measure of the stiffness of a material and is defined as the ratio of tensile or compressive stress to longitudinal strain.
3. Shear modulus is defined as the ratio of shearing stress to shearing strain and measures a material's resistance to deformation via shear forces.
- Elasticity is the property of an object to regain its original shape after a deforming force is removed. The limit of deforming force where an object fully regains its shape is called the elastic limit.
- Stress is defined as the internal restoring force acting per unit area of a deformed object. Stress can be normal or tangential depending on the direction of the deforming force.
- Strain is defined as the fractional change in configuration of an object. The ratio of stress to strain within the elastic limit is a material property called modulus of elasticity or Young's modulus.
Effect of Coarse Aggregate Size on the Compressive Strength and the Flexural ...IJERA Editor
Concrete structures deflect, crack, and loose stiffness when subjected to external load. Loss of flexural strength of concrete is largely responsible for cracks in structure. In reinforced concrete structures, the mix proportions of the materials of the concrete and aggregate type determine the compressive strength while the composite action of concrete and steel reinforcement supplies the flexural strength. In occasion of loss of stiffness, steel reinforcement no longer supports flexural stresses; concrete in turn is subjected to flexure. The compressive strength and flexural strength therefore play a crucial role. Effect of varying coarse aggregate size on the flexural and compressive strengths of concrete beam was investigated. Concrete cubes and beams were produced in accordance with BS 1881-108 (1983) and ASTM C293 with varying aggregate sizes 9.0mm, 13.2mm, 19mm, 25.0mm and 37.5mm, using a standard mould of internal dimension 150x150x150 for the concrete cubes and a mould of internal dimension of 150 x 150 x 750mm for the reinforced concrete beam. The water cement ratio was kept at 0.65 with a mix proportion of 1:2:4. The specimen produced were all subjected to curing in water for 28days and were all tested to determine the compressive strength and flexural strength using Universal Testing Machine. Compressive strength of cubes is 21.26N/mm2, 23.41N/mm2, 23.66N/mm2, and 24.31N/mm2 for coarse aggregate sizes 13.2mm, 19mm, 25.0mm and 37.5mm respectively. That of flexural strength of test beams is 4.93N/mm2, 4.78N/mm2, 4.53N/mm2, 4.49N/mm2, 4.40N/mm2 respectively. In conclusion, concrete to be used mostly to resist flexural stresses should be made of finer coarse aggregates.
This document defines key terms related to Young's modulus including:
- Stress is the force applied per cross-sectional area of a material.
- Strain is the extension in length resulting from stress.
- Brittle materials break without plastic deformation.
- Elastic materials return to their original shape after deformation.
It also provides examples of materials that exhibit properties such as being stiff, elastic, plastic, ductile, malleable, strong, brittle, tough, smooth, and durable. The document outlines measurements needed to calculate stress and strain and discusses working out uncertainty when multiplying or dividing units.
Class 11 Mechanical Properties of Solids MobViewManik Bhola
The document contains a physics test on mechanical properties of solids with 18 multiple choice questions covering topics like Young's modulus, stress, strain, Hooke's law, ductility, and brittleness. It also includes conceptual questions about topics such as why railway tracks use wooden sleepers, how parachutes help during falling, and whether a body can be shielded from gravity. There are explanations provided for the conceptual questions.
The document summarizes different hardness testing methods. It describes macrohardness tests like Rockwell, Brinell and Vickers which use indenters with loads over 1kg. Microhardness tests like Knoop and Vickers use loads under 1kg for small parts. The Rockwell test measures depth changes from minor and major loads. Brinell uses a steel ball under load and measures indentation diameter. Vickers uses a pyramidal indenter and calculates hardness from diagonal lengths. Hardness is related to properties like tensile strength and can estimate them for materials like steel. Experiments will test and calculate hardness values for various materials using these methods.
This document discusses comminution mechanisms, which are the ways that particles fracture during size reduction processes. It describes four main mechanisms: shatter (impact fracture), cleavage, attrition, and abrasion. Shatter occurs via high-speed impacts and produces a broad size distribution. Cleavage happens under lower compression and yields a narrower size range. Attrition is particle wear during interactions like grinding. The document explains the factors that influence fracture, such as flaws and applied stress. It also reviews theories of how energy relates to breakage. The goal is to understand particle fracture to improve efficiency of comminution equipment and processes.
This document summarizes an experimental study and numerical simulation of a single-rod damper that uses an elastomer particle assemblage instead of oil. The study investigated the damper force characteristics of a prototype dual-chamber single-rod damper with elastomer particles in one chamber. Experiments varied the packing ratio of particles, vibration frequency, particle material properties, and stroke center position. A numerical simulation using the discrete element method modeled particle behavior inside the damper and agreed with experimental results, showing large hysteresis in damper force due to particle deformation.
1. Hooke's law states that the stress and strain of a material are proportional for small deformations.
2. Young's modulus is a measure of the stiffness of a material and is defined as the ratio of tensile or compressive stress to longitudinal strain.
3. Shear modulus is defined as the ratio of shearing stress to shearing strain and measures a material's resistance to deformation via shear forces.
- Elasticity is the property of an object to regain its original shape after a deforming force is removed. The limit of deforming force where an object fully regains its shape is called the elastic limit.
- Stress is defined as the internal restoring force acting per unit area of a deformed object. Stress can be normal or tangential depending on the direction of the deforming force.
- Strain is defined as the fractional change in configuration of an object. The ratio of stress to strain within the elastic limit is a material property called modulus of elasticity or Young's modulus.
Effect of Coarse Aggregate Size on the Compressive Strength and the Flexural ...IJERA Editor
Concrete structures deflect, crack, and loose stiffness when subjected to external load. Loss of flexural strength of concrete is largely responsible for cracks in structure. In reinforced concrete structures, the mix proportions of the materials of the concrete and aggregate type determine the compressive strength while the composite action of concrete and steel reinforcement supplies the flexural strength. In occasion of loss of stiffness, steel reinforcement no longer supports flexural stresses; concrete in turn is subjected to flexure. The compressive strength and flexural strength therefore play a crucial role. Effect of varying coarse aggregate size on the flexural and compressive strengths of concrete beam was investigated. Concrete cubes and beams were produced in accordance with BS 1881-108 (1983) and ASTM C293 with varying aggregate sizes 9.0mm, 13.2mm, 19mm, 25.0mm and 37.5mm, using a standard mould of internal dimension 150x150x150 for the concrete cubes and a mould of internal dimension of 150 x 150 x 750mm for the reinforced concrete beam. The water cement ratio was kept at 0.65 with a mix proportion of 1:2:4. The specimen produced were all subjected to curing in water for 28days and were all tested to determine the compressive strength and flexural strength using Universal Testing Machine. Compressive strength of cubes is 21.26N/mm2, 23.41N/mm2, 23.66N/mm2, and 24.31N/mm2 for coarse aggregate sizes 13.2mm, 19mm, 25.0mm and 37.5mm respectively. That of flexural strength of test beams is 4.93N/mm2, 4.78N/mm2, 4.53N/mm2, 4.49N/mm2, 4.40N/mm2 respectively. In conclusion, concrete to be used mostly to resist flexural stresses should be made of finer coarse aggregates.
This document defines key terms related to Young's modulus including:
- Stress is the force applied per cross-sectional area of a material.
- Strain is the extension in length resulting from stress.
- Brittle materials break without plastic deformation.
- Elastic materials return to their original shape after deformation.
It also provides examples of materials that exhibit properties such as being stiff, elastic, plastic, ductile, malleable, strong, brittle, tough, smooth, and durable. The document outlines measurements needed to calculate stress and strain and discusses working out uncertainty when multiplying or dividing units.
Class 11 Mechanical Properties of Solids MobViewManik Bhola
The document contains a physics test on mechanical properties of solids with 18 multiple choice questions covering topics like Young's modulus, stress, strain, Hooke's law, ductility, and brittleness. It also includes conceptual questions about topics such as why railway tracks use wooden sleepers, how parachutes help during falling, and whether a body can be shielded from gravity. There are explanations provided for the conceptual questions.
The document summarizes different hardness testing methods. It describes macrohardness tests like Rockwell, Brinell and Vickers which use indenters with loads over 1kg. Microhardness tests like Knoop and Vickers use loads under 1kg for small parts. The Rockwell test measures depth changes from minor and major loads. Brinell uses a steel ball under load and measures indentation diameter. Vickers uses a pyramidal indenter and calculates hardness from diagonal lengths. Hardness is related to properties like tensile strength and can estimate them for materials like steel. Experiments will test and calculate hardness values for various materials using these methods.
This document discusses comminution mechanisms, which are the ways that particles fracture during size reduction processes. It describes four main mechanisms: shatter (impact fracture), cleavage, attrition, and abrasion. Shatter occurs via high-speed impacts and produces a broad size distribution. Cleavage happens under lower compression and yields a narrower size range. Attrition is particle wear during interactions like grinding. The document explains the factors that influence fracture, such as flaws and applied stress. It also reviews theories of how energy relates to breakage. The goal is to understand particle fracture to improve efficiency of comminution equipment and processes.
This document provides an overview of comminution, the process of reducing the size of raw materials, including the basic concepts, theories, and trends. It discusses crushing and grinding processes, principles of comminution involving fracture mechanics, and methods for measuring grindability including Bond work index and SAG power index tests.
Mechanical properties of orthodontic biomaterials (2)Santosh Kumar
This document discusses the mechanical properties of orthodontic biomaterials. It defines mechanical properties as measures of a material's resistance to deformation or fracture under applied forces. The key mechanical properties discussed are:
1. Elastic properties like elastic modulus, resilience, and Poisson's ratio which measure a material's elastic deformation in response to stress.
2. Plastic properties like percent elongation and hardness which measure a material's permanent or irreversible deformation after stress is removed.
3. Strength properties like yield strength and fracture toughness which indicate the stress level required to cause plastic deformation or fracture.
Standard tests for measuring properties like hardness, strength and toughness are also outlined. In summary, the document provides an overview
This document discusses principles of comminution and crushing in mineral processing. It describes the key theories of comminution including Kick's law, Rittinger's theory, and Bond's theory. It then focuses on primary crushers, describing the main types of jaw and gyratory crushers. Details are provided on jaw crusher construction and the differences between single toggle and double toggle jaw crushers. The document also discusses secondary and tertiary crushing operations.
Long term strength and durability evaluation of sisal fibre compositesIAEME Publication
This document discusses a study on the long-term strength and durability of sisal fiber cement composites. The study evaluated the compressive, flexural, split-tensile, impact, and flexural strengths of cement mortar composites containing 0.25-2.0% sisal fibers at ages of 28, 56, 90, and 120 days. The durability of the composites was also evaluated by exposing specimens to an alkaline solution and measuring changes in properties. The results showed that strengths generally increased with fiber content up to 0.5% and with age. Durability was assessed by comparing properties before and after alkaline exposure. The study provides reference data on how sisal fibers influence the long-term properties
This document provides an overview of the physical properties of dental materials. It discusses topics like the structure of matter, interatomic bonds, adhesion and bonding, concepts of stress and strain, and rheology. The document is intended to explain the underlying physics and chemistry that determine the mechanical, thermal, optical and other observable qualities of dental materials. It focuses on topics like crystalline structure, bonding forces, surface energy, wetting, and how stresses and strains impact materials at the atomic level. The overall aim is to describe the fundamental physical principles that govern the behavior and performance of different dental materials.
This document discusses plastic instability in uniaxial tension testing of materials. It defines true stress and strain, which account for changes in cross-sectional area during tension, and explains how they relate to engineering stress and strain. The condition for plastic instability is derived as the maximum in the true stress-strain curve where the rate of true stress increase with respect to true strain is equal to the true stress. This occurs at a uniform true strain value called the instability strain. Examples of true stress-strain curves and determinations of the strain hardening exponent are also provided.
The document summarizes a summer training report on the characterization of 8 mole% yttria stabilized zirconia obtained from different sources. The objectives were to characterize and compare YSZ powders from ISRO, IRE and TOSOH, and to optimize sintering conditions to achieve high density pellets suitable for use as a solid oxide fuel cell electrolyte. Characterization techniques included tap density measurement, BET surface area analysis, X-ray diffraction for phase analysis, particle size distribution analysis, and density measurement of sintered pellets.
This document discusses the mechanical properties of viscoelastic materials. It covers topics like stress/strain behavior, creep, toughness, reinforcement, and modifiers. It explains how polymer chemistry, structures, and properties influence product performance. Key factors that determine a plastic's mechanical response are intermolecular forces, temperature, time under load, degree of crystallinity, and molecular weight. A plastic can behave as an elastic solid, viscoelastic solid, viscoelastic fluid, or viscous fluid depending on these factors. Tests like tensile testing, impact testing, and dynamic mechanical analysis are used to characterize mechanical properties.
This document discusses various mechanical properties of materials including elastic deformation, engineering strain, tensile strength, toughness, yielding, modulus of elasticity, Poisson's ratio, ductility, malleability, hardness, and fatigue. It provides definitions and explanations of these key material properties and how they relate to a material's behavior under stress or loads over time.
This study investigated the effects of coir mat and coir fibre reinforcement on the shear strength of dry sand. Direct shear tests were conducted on sand specimens with randomly distributed coir fibres of varying lengths (10mm, 20mm, 30mm) and fibre contents (0.05%, 0.1%, 0.2%, 0.3%). The results showed that fibre reinforcement increased the angle of internal friction and peak shear stress of sand compared to unreinforced sand. The maximum increases were observed at a fibre content of 0.2%. Additional direct shear tests examined the effects of coir mats with different opening sizes (10mm, 20mm, 30mm) placed at the interface. The results provide insight into the
Mechanical properties of dental material المحاضرة الأولىLama K Banna
The document discusses various mechanical properties of dental materials including strain, stress, stress-strain curves, hardness, and strength. It provides definitions and explanations of key terms:
1) Strain and stress occur when forces are applied to materials, causing deformation and internal resisting forces. Stress-strain curves plot these values to compare material properties.
2) Properties like elasticity, strength, and brittleness are determined from the curves. Hardness tests measure material resistance to indentation or scratching.
3) Common tests include Brinell, Knoop, and Rockwell hardness tests as well as transverse strength and diametral compression tests for brittle materials. Understanding material mechanics guides selection of suitable dental materials
Experiment NO:6 describes a compression test performed on an anisotropic wooden material to determine its compressive strength when force is applied both parallel and perpendicular to its fibers. When force was applied perpendicular to the fibers, the wooden block failed at a compressive strength of 4.7712x107 N/m2. When applied parallel to the fibers, the failure strength was lower at 1.204x107 N/m2. Detailed load-deformation data is provided in tables showing that the material can withstand over 10 times more load when compressed parallel rather than perpendicular to its fibers, as the fibers act like columns parallel to the load.
This document provides an overview of the various physical properties of dental materials, including rheological properties like viscosity and viscoelasticity, thermal properties such as thermal conductivity and coefficient of thermal expansion, mechanical properties like modulus of elasticity and hardness, electrical properties like galvanism, and chemical properties such as corrosion and tarnish. It discusses these properties in the context of how they impact dental materials during storage, mixing, setting and as a set material. The properties are important to consider when selecting materials to ensure their successful performance for the intended dental application.
This document describes Standard Test Method E 384 for determining microindentation hardness of materials. The standard covers using Knoop and Vickers indenters to make indentations between 1-1000 gf force. Hardness is calculated based on indentation size and geometry. Key points:
- Hardness is determined by dividing force by projected area or surface area of indentation for Knoop or Vickers respectively.
- Equipment must precisely control low forces and indentation size must be measured via microscope.
- Specimens must be flat and polished to accurately measure indentation diagonals and calculate hardness.
- Multiple sources of error exist and can affect accuracy of results, including force variation, indenter geometry, and measurement errors. Standard aims
1) The document discusses various mechanical properties of dental materials including elastic properties like elastic modulus and plastic properties like yield strength.
2) Mechanical properties are quantified using concepts of stress and strain, and different tests are used to measure properties like hardness, tensile strength, and impact resistance.
3) Key mechanical properties discussed include elastic modulus, proportional limit, yield strength, ductility, toughness, and hardness. Different tests for measuring these properties are also described.
Exaral and shear cap. of conc.beams with volcanic tuff) copyAlexander Decker
The document describes an experimental study that investigated the effect of three types of volcanic tuff as a replacement for fine aggregate in reinforced concrete beams. Beams were made with 0% and 20% replacement of fine aggregate with brown, gray, or yellow volcanic tuff. The concrete strengths tested were 20, 30, 40, and 50 MPa. Test results showed that replacing 20% of fine aggregate with volcanic tuff improved the flexural and shear capacities of the beams compared to the control beams without tuff. The degree of improvement varied between 3-26% depending on the concrete strength and type of volcanic tuff used.
This document discusses a study that evaluated the effect of indentation size on the microhardness values of two viscoelastic dental materials (a resin composite and resin modified glass ionomer cement) under different loads and holding times. Vickers and Knoop microhardness tests were used to assess the materials at loads of 100, 200, and 300g and times of 10, 20, and 30 seconds. The results showed that microhardness values for both materials were significantly affected by the load for Vickers hardness tests. For Knoop hardness tests, only the composite showed significant load-dependence while the resin modified glass ionomer cement did not. The optimal load and time to determine microhardness could not be conclusively determined for either
Anisotropy of Coercive Force of Single Crystals and Sheets of Silicon Iron wi...ijeljournal
In this paper we investigate the regularities of anisotropy of coercive force both single crystals with the orientation of surfaces parallel (001) so and the polycrystalline sheets of alloy Fe - 3% Si with different texture. The mechanisms of anisotropy of coercive force are discussed.
This document describes an experimental study that evaluated the material stability of different aluminum alloys for ultra precision applications. Specifically, it tested 7075-T7351, 7075-T6 and 6061-T6 aluminum alloys under cyclic loading conditions. The study used a custom test machine with sensors to precisely measure deformation in the aluminum alloy samples. Results showed that the different alloys exhibited inelastic and plastic deformation under loading and unloading cycles. Inelastic deformation recovered after unloading, while plastic deformation remained. The document aims to determine the most suitable aluminum alloy to replace steel components in high frequency weighing scales.
Profile modification of adhesively bonded cylindrical joint for maximum torqu...IJMER
International Journal of Modern Engineering Research (IJMER) is Peer reviewed, online Journal. It serves as an international archival forum of scholarly research related to engineering and science education.
International Journal of Modern Engineering Research (IJMER) covers all the fields of engineering and science: Electrical Engineering, Mechanical Engineering, Civil Engineering, Chemical Engineering, Computer Engineering, Agricultural Engineering, Aerospace Engineering, Thermodynamics, Structural Engineering, Control Engineering, Robotics, Mechatronics, Fluid Mechanics, Nanotechnology, Simulators, Web-based Learning, Remote Laboratories, Engineering Design Methods, Education Research, Students' Satisfaction and Motivation, Global Projects, and Assessment…. And many more.
This document provides an overview of comminution, the process of reducing the size of raw materials, including the basic concepts, theories, and trends. It discusses crushing and grinding processes, principles of comminution involving fracture mechanics, and methods for measuring grindability including Bond work index and SAG power index tests.
Mechanical properties of orthodontic biomaterials (2)Santosh Kumar
This document discusses the mechanical properties of orthodontic biomaterials. It defines mechanical properties as measures of a material's resistance to deformation or fracture under applied forces. The key mechanical properties discussed are:
1. Elastic properties like elastic modulus, resilience, and Poisson's ratio which measure a material's elastic deformation in response to stress.
2. Plastic properties like percent elongation and hardness which measure a material's permanent or irreversible deformation after stress is removed.
3. Strength properties like yield strength and fracture toughness which indicate the stress level required to cause plastic deformation or fracture.
Standard tests for measuring properties like hardness, strength and toughness are also outlined. In summary, the document provides an overview
This document discusses principles of comminution and crushing in mineral processing. It describes the key theories of comminution including Kick's law, Rittinger's theory, and Bond's theory. It then focuses on primary crushers, describing the main types of jaw and gyratory crushers. Details are provided on jaw crusher construction and the differences between single toggle and double toggle jaw crushers. The document also discusses secondary and tertiary crushing operations.
Long term strength and durability evaluation of sisal fibre compositesIAEME Publication
This document discusses a study on the long-term strength and durability of sisal fiber cement composites. The study evaluated the compressive, flexural, split-tensile, impact, and flexural strengths of cement mortar composites containing 0.25-2.0% sisal fibers at ages of 28, 56, 90, and 120 days. The durability of the composites was also evaluated by exposing specimens to an alkaline solution and measuring changes in properties. The results showed that strengths generally increased with fiber content up to 0.5% and with age. Durability was assessed by comparing properties before and after alkaline exposure. The study provides reference data on how sisal fibers influence the long-term properties
This document provides an overview of the physical properties of dental materials. It discusses topics like the structure of matter, interatomic bonds, adhesion and bonding, concepts of stress and strain, and rheology. The document is intended to explain the underlying physics and chemistry that determine the mechanical, thermal, optical and other observable qualities of dental materials. It focuses on topics like crystalline structure, bonding forces, surface energy, wetting, and how stresses and strains impact materials at the atomic level. The overall aim is to describe the fundamental physical principles that govern the behavior and performance of different dental materials.
This document discusses plastic instability in uniaxial tension testing of materials. It defines true stress and strain, which account for changes in cross-sectional area during tension, and explains how they relate to engineering stress and strain. The condition for plastic instability is derived as the maximum in the true stress-strain curve where the rate of true stress increase with respect to true strain is equal to the true stress. This occurs at a uniform true strain value called the instability strain. Examples of true stress-strain curves and determinations of the strain hardening exponent are also provided.
The document summarizes a summer training report on the characterization of 8 mole% yttria stabilized zirconia obtained from different sources. The objectives were to characterize and compare YSZ powders from ISRO, IRE and TOSOH, and to optimize sintering conditions to achieve high density pellets suitable for use as a solid oxide fuel cell electrolyte. Characterization techniques included tap density measurement, BET surface area analysis, X-ray diffraction for phase analysis, particle size distribution analysis, and density measurement of sintered pellets.
This document discusses the mechanical properties of viscoelastic materials. It covers topics like stress/strain behavior, creep, toughness, reinforcement, and modifiers. It explains how polymer chemistry, structures, and properties influence product performance. Key factors that determine a plastic's mechanical response are intermolecular forces, temperature, time under load, degree of crystallinity, and molecular weight. A plastic can behave as an elastic solid, viscoelastic solid, viscoelastic fluid, or viscous fluid depending on these factors. Tests like tensile testing, impact testing, and dynamic mechanical analysis are used to characterize mechanical properties.
This document discusses various mechanical properties of materials including elastic deformation, engineering strain, tensile strength, toughness, yielding, modulus of elasticity, Poisson's ratio, ductility, malleability, hardness, and fatigue. It provides definitions and explanations of these key material properties and how they relate to a material's behavior under stress or loads over time.
This study investigated the effects of coir mat and coir fibre reinforcement on the shear strength of dry sand. Direct shear tests were conducted on sand specimens with randomly distributed coir fibres of varying lengths (10mm, 20mm, 30mm) and fibre contents (0.05%, 0.1%, 0.2%, 0.3%). The results showed that fibre reinforcement increased the angle of internal friction and peak shear stress of sand compared to unreinforced sand. The maximum increases were observed at a fibre content of 0.2%. Additional direct shear tests examined the effects of coir mats with different opening sizes (10mm, 20mm, 30mm) placed at the interface. The results provide insight into the
Mechanical properties of dental material المحاضرة الأولىLama K Banna
The document discusses various mechanical properties of dental materials including strain, stress, stress-strain curves, hardness, and strength. It provides definitions and explanations of key terms:
1) Strain and stress occur when forces are applied to materials, causing deformation and internal resisting forces. Stress-strain curves plot these values to compare material properties.
2) Properties like elasticity, strength, and brittleness are determined from the curves. Hardness tests measure material resistance to indentation or scratching.
3) Common tests include Brinell, Knoop, and Rockwell hardness tests as well as transverse strength and diametral compression tests for brittle materials. Understanding material mechanics guides selection of suitable dental materials
Experiment NO:6 describes a compression test performed on an anisotropic wooden material to determine its compressive strength when force is applied both parallel and perpendicular to its fibers. When force was applied perpendicular to the fibers, the wooden block failed at a compressive strength of 4.7712x107 N/m2. When applied parallel to the fibers, the failure strength was lower at 1.204x107 N/m2. Detailed load-deformation data is provided in tables showing that the material can withstand over 10 times more load when compressed parallel rather than perpendicular to its fibers, as the fibers act like columns parallel to the load.
This document provides an overview of the various physical properties of dental materials, including rheological properties like viscosity and viscoelasticity, thermal properties such as thermal conductivity and coefficient of thermal expansion, mechanical properties like modulus of elasticity and hardness, electrical properties like galvanism, and chemical properties such as corrosion and tarnish. It discusses these properties in the context of how they impact dental materials during storage, mixing, setting and as a set material. The properties are important to consider when selecting materials to ensure their successful performance for the intended dental application.
This document describes Standard Test Method E 384 for determining microindentation hardness of materials. The standard covers using Knoop and Vickers indenters to make indentations between 1-1000 gf force. Hardness is calculated based on indentation size and geometry. Key points:
- Hardness is determined by dividing force by projected area or surface area of indentation for Knoop or Vickers respectively.
- Equipment must precisely control low forces and indentation size must be measured via microscope.
- Specimens must be flat and polished to accurately measure indentation diagonals and calculate hardness.
- Multiple sources of error exist and can affect accuracy of results, including force variation, indenter geometry, and measurement errors. Standard aims
1) The document discusses various mechanical properties of dental materials including elastic properties like elastic modulus and plastic properties like yield strength.
2) Mechanical properties are quantified using concepts of stress and strain, and different tests are used to measure properties like hardness, tensile strength, and impact resistance.
3) Key mechanical properties discussed include elastic modulus, proportional limit, yield strength, ductility, toughness, and hardness. Different tests for measuring these properties are also described.
Exaral and shear cap. of conc.beams with volcanic tuff) copyAlexander Decker
The document describes an experimental study that investigated the effect of three types of volcanic tuff as a replacement for fine aggregate in reinforced concrete beams. Beams were made with 0% and 20% replacement of fine aggregate with brown, gray, or yellow volcanic tuff. The concrete strengths tested were 20, 30, 40, and 50 MPa. Test results showed that replacing 20% of fine aggregate with volcanic tuff improved the flexural and shear capacities of the beams compared to the control beams without tuff. The degree of improvement varied between 3-26% depending on the concrete strength and type of volcanic tuff used.
This document discusses a study that evaluated the effect of indentation size on the microhardness values of two viscoelastic dental materials (a resin composite and resin modified glass ionomer cement) under different loads and holding times. Vickers and Knoop microhardness tests were used to assess the materials at loads of 100, 200, and 300g and times of 10, 20, and 30 seconds. The results showed that microhardness values for both materials were significantly affected by the load for Vickers hardness tests. For Knoop hardness tests, only the composite showed significant load-dependence while the resin modified glass ionomer cement did not. The optimal load and time to determine microhardness could not be conclusively determined for either
Anisotropy of Coercive Force of Single Crystals and Sheets of Silicon Iron wi...ijeljournal
In this paper we investigate the regularities of anisotropy of coercive force both single crystals with the orientation of surfaces parallel (001) so and the polycrystalline sheets of alloy Fe - 3% Si with different texture. The mechanisms of anisotropy of coercive force are discussed.
This document describes an experimental study that evaluated the material stability of different aluminum alloys for ultra precision applications. Specifically, it tested 7075-T7351, 7075-T6 and 6061-T6 aluminum alloys under cyclic loading conditions. The study used a custom test machine with sensors to precisely measure deformation in the aluminum alloy samples. Results showed that the different alloys exhibited inelastic and plastic deformation under loading and unloading cycles. Inelastic deformation recovered after unloading, while plastic deformation remained. The document aims to determine the most suitable aluminum alloy to replace steel components in high frequency weighing scales.
Profile modification of adhesively bonded cylindrical joint for maximum torqu...IJMER
International Journal of Modern Engineering Research (IJMER) is Peer reviewed, online Journal. It serves as an international archival forum of scholarly research related to engineering and science education.
International Journal of Modern Engineering Research (IJMER) covers all the fields of engineering and science: Electrical Engineering, Mechanical Engineering, Civil Engineering, Chemical Engineering, Computer Engineering, Agricultural Engineering, Aerospace Engineering, Thermodynamics, Structural Engineering, Control Engineering, Robotics, Mechatronics, Fluid Mechanics, Nanotechnology, Simulators, Web-based Learning, Remote Laboratories, Engineering Design Methods, Education Research, Students' Satisfaction and Motivation, Global Projects, and Assessment…. And many more.
This document provides a practicum final report on experiments measuring the Young's modulus and torsional constant of copper. For Young's modulus, the stress-strain relationship was examined using two methods: central flexing and tip flexing of copper rods. For the torsional constant, the oscillation period of a copper disc suspended by a wire was measured at varying angles of twist and wire lengths. Equations for stress, strain, Young's modulus, and torsional constant are provided. Tables show the raw experimental data collected and calculations of the measured values of Young's modulus and torsional constant.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Torsional evaluation of Tapered Composite Cone using Finite Element AnalysisIOSR Journals
Composite material is one of the most important and economical material for the various application
due to its favorable properties .Recently many researches are going on the various properties of the these
materials .In this paper an anisotropic behavior of the composite tube is to be modeled and analysis is to be
performed under torsional loading conditions. Torsion is a tricky phenomenon in composite cylinders as the
twist effects and their interactions with composite shells induce complex stress patterns. The objective behind
the study is to understand interaction of conical angle, length of tube and torsional moment .it also includes
comparative analysis of deformation and stresses developed in tapered composite cone due to use of various
materials like steel, orthotropic composite and laminated composite etc. The effect of taper angle, thickness of
the tube and fiber orientations in case of laminated composite is studied by using finite element analysis (ANSYS
software). The finite element analysis is especially versatile and efficient for the analysis of complex structural
behavior of the composite laminated structures. It is found that deformation in case of laminated composite and
deformation in between steel and laminated composite cone. At membrane stresses are observed at the middle of
cone in length direction for three materials.
Vibrational Analysis Of Cracked Rod Having Circumferential Crack IDES Editor
The frequency ratio of torsional vibration of a rod without crack and of rod with crack subjected to torque at the free end for various crack depth and varying crack location is investigated. It is found that even a cracked of small depth is
dangerous at the fixed end, also as the crack depth is increases more than 50% of diameter of rod there is a considerable drop in natural frequency of the rod .
Investigation of Extrusion of Lead experimentally from Round section through ...inventy
ABSTRACT :The changes of die angle, area reduction in dies, loading rate on the final extruded products, extrusion pressures of lead of circular cross sections has been investigated experimentally. The proposed method is successfully adapted to the forward extrusion of the equilateral triangular section from round billet through converging dies of different area reductions. Computation of extrusion pressure at various area reductions and calculations of different parameters (stress, strain etc.) in wet condition.
Keywords - Extrusion of Triangular section, Converging Dies at different area reductions, Friction Factor, Extrusion Pressure
Design and Analysis of Auger in KAMCO Power Tillerinventy
Research Inventy : International Journal of Engineering and Science is published by the group of young academic and industrial researchers with 12 Issues per year. It is an online as well as print version open access journal that provides rapid publication (monthly) of articles in all areas of the subject such as: civil, mechanical, chemical, electronic and computer engineering as well as production and information technology. The Journal welcomes the submission of manuscripts that meet the general criteria of significance and scientific excellence. Papers will be published by rapid process within 20 days after acceptance and peer review process takes only 7 days. All articles published in Research Inventy will be peer-reviewed.
IRJET- Investigation and Analysis of Multiple Cracks in Cantilever Beam by us...IRJET Journal
The document investigates the free vibration analysis of uniform and stepped cantilever beams with single and multiple cracks using finite element modeling. An experimental study is conducted to validate the numerical results. The presence of cracks reduces the local stiffness matrix and alters the natural frequencies of the system. Results show that as crack depth increases, frequency reduction also increases for both uniform and stepped beams. Natural frequencies are more influenced by crack location than depth. Cracks near fixed ends have a greater effect on the first natural frequency mode compared to cracks near free ends.
12-2-Publication-Experimental Analysis of Explosive FormingSaeed Jabalamelian
This study numerically simulates and experimentally tests the explosive hydroforming process used to form torispherical heads made of aluminum alloy AA5083. Finite element models using LS-DYNA software were developed to simulate the process, applying the Johnson-Cook and Modified Zerilli-Armstrong constitutive models. The models were verified against experimental tests. The simulation captured most material behaviors under different stress states but did not fully describe the transient zone between tension and compression. The predicted width of the transient rim was smaller than seen experimentally. Overall the blast loading simulation showed good agreement with Cole's relation for underwater detonation of small charges, with 95% accuracy.
The document analyzes the effect of vibration on the performance of a PEM fuel cell. It performs a modal analysis to determine natural frequencies below 1kHz. Harmonic analysis at 4g acceleration for 1 hour shows maximum deformations. Accounting for bolt loosening due to vibrations changes contact pressure profiles. Estimates include a hydrogen leakage rate of 0.16778 L/hr due to vibrations at resonance frequencies. The study provides a framework to evaluate fuel cell design for mobile applications operating in vibration environments.
Finite Element Analysis of honeycomb using AbaqusUdayan Ghosh
Prepared 3D CAD model of honeycomb in SolidWorks; studied structural behavior for static and dynamic loading
Performed mesh refinement, verification, validation and error analysis for the FEA
Influence of contact friction conditions on thin profile simulationVan Canh Nguyen
The paper presents the development of the Finite Element model for simulation of thin
aluminium profile extrusion of both solid and hollow shapes. The analysis has shown that the material
flow in simulation is very dependent on the friction model. Experimental and theoretical studies show
that friction traction on the interface between the tool and the deformed material can be represented as
a combination of adhesive friction force and the force that is required to deform surface asperities. In
aluminium extrusion we can clearly distinguish two different areas with respect to friction conditions
such as sticking and sliding and transient zones between them. The lengths of these zones are also
dependent on variation of the choke angle and actual thickness of the profile. To get these values the
material flow problem is to be coupled with the simulation of the tools deformation. A series of
experiments with specially designed tools have been done to investigate how the bearing length and
choke angle may influence the extension of different friction zones and by these means vary the
material flow pattern. The friction models have also been tested with industrial profiles of complex
shapes and have shown good correspondence to reality.
This paper involves an experimental investigation on the flexural behaviour of curved beams and comparison of its results with conventional beams. Curved beams of size 1200 x 150 x 100 mm with varying initial curvature as 4000mm, 2000mm and the concrete strength as M40 is considered. Various reinforcement are provided in the curved beams to predict which reinforcement detail would give more resistant over maximum loading. The material properties of cement, fine aggregate, coarse aggregate and the compressive strength of concrete cube were found out. A total of 12 specimens of curved beams were casted with various combination of reinforcement along with three control specimens. The beams are tested under two point loading both horizontally and vertically. The deflection and maximum moment carrying capacity are investigated to understand its strength. Also analytical modelling is done to determine the ultimate moment carrying capacity using Finite Element Software ABAQUS to compare with the experimental model.
This document discusses the design and working of a magnetic suspension system for a two-wheeler vehicle. It aims to reduce shocks transmitted to the vehicle from irregular road surfaces. The system uses electromagnets as passive dampers between the sprung and unsprung vehicle masses. This helps absorb shocks and improve ride comfort over traditional spring absorbers. The document outlines the objectives, literature review on magnetic suspension systems, design of the main coil spring, magnets, hollow shaft, and conclusions on developing a low-cost magnetic suspension system with minimized size.
Estimating damping in structure made of different m aterials (steel,brass,aluminum) and processes sti ll remains as one of the biggest challengers. All mate rials posses certain amount of internal damping,wh ich manifested as dissipation of energy from the system . This energy in a vibratory system is either dissipated into heat or radiated away from the syst em. Material damping or internal damping contribute s to about 10-15% of total system damping. Cantilever beams of required size & shape are prepared for experimental purpose & damping ratio is investigate d. Damping ratio is determined by half-power bandwidth method. It is observed that damping ratio is higher for steel than brass than aluminum.
Tilting of arm is easily available in existing design as working arm is for shifting the big sheetmetal body
from one station to another to get drilled. Now task is to design hub which allows turning of robotic arm along with
tilting without affecting its working behavior. In this study design and evaluation of hub body formed by weldment
sheet metal components is done. validation of strength is done by carrying out static structural analysis in ANSYS.
This document describes using the finite difference method (FDM) to analyze Timoshenko beam theory. The FDM approximates differential equations governing beam behavior with finite differences at discrete grid points along the beam. Traditionally, boundary conditions rather than governing equations are applied at beam ends in FDM, reducing accuracy. The presented model introduces additional grid points at beam ends and discontinuities to apply governing equations at ends. First-order analysis of forces and deformations is conducted. Second-order and vibration analyses are also presented using the model. A direct time integration method enables forced vibration analysis with damping. Results show good agreement with other studies when grid is refined.
Experimental and numerical analysis of expanded pipe using rigid conical shap...ahmed Ibrahim
The experimental and numerical analysis was performed on pipes suffering large plastic deformation through expanding them using rigid conical shaped mandrels, with three different
cone angles (15◦, 25◦, 35◦) and diameters (15, 17, 20) mm. The experimental test for the strain results investigated the expanded areas. A numerical solution of the pipes expansion process was
also investigated using the commercial finite element software ANSYS. The strains were
measured for each case experimentally by stamping the mesh on the pipe after expanding, then compared with Ansys results. No cracks were generated during the process with the selected
angles. It can be concluded that the strain decreased with greater angles of conical shape and an increase in expansion ratio results in an increase of expansion force and a decrease in the pipe thickness and length resulting in pipe thinning and shortening. Good agreement is evident between experimental and ANSYS results within discrepancy (16.90017%) in the X direction and (27.68698%) in the Y direction. Also, the stress distribution is investigated and it can be concluded that the case of Diameter (Do cone) = 35mm and (A) = α = 15° is the optimum.K
FRACTURE MECHANICS OF NANO-SILICA PARTICLES IN REINFORCED EPOXIES Jordan Suls
This document summarizes a study that used finite element modeling to examine how different levels of particle dispersion (evenly dispersed, moderately clumped, and severely clumped) affect the fracture mechanics of nanosilica particle reinforced epoxies. Three models were created in Abaqus with the different dispersion levels and subjected to tensile loading. The results found that the evenly dispersed model had the highest fracture toughness, as indicated by its ability to withstand a greater force at similar displacements. This was because the clumped models developed large stress regions around the clumps that caused earlier debonding of the particle-matrix interfaces and faster crack propagation.
Null Bangalore | Pentesters Approach to AWS IAMDivyanshu
#Abstract:
- Learn more about the real-world methods for auditing AWS IAM (Identity and Access Management) as a pentester. So let us proceed with a brief discussion of IAM as well as some typical misconfigurations and their potential exploits in order to reinforce the understanding of IAM security best practices.
- Gain actionable insights into AWS IAM policies and roles, using hands on approach.
#Prerequisites:
- Basic understanding of AWS services and architecture
- Familiarity with cloud security concepts
- Experience using the AWS Management Console or AWS CLI.
- For hands on lab create account on [killercoda.com](https://killercoda.com/cloudsecurity-scenario/)
# Scenario Covered:
- Basics of IAM in AWS
- Implementing IAM Policies with Least Privilege to Manage S3 Bucket
- Objective: Create an S3 bucket with least privilege IAM policy and validate access.
- Steps:
- Create S3 bucket.
- Attach least privilege policy to IAM user.
- Validate access.
- Exploiting IAM PassRole Misconfiguration
-Allows a user to pass a specific IAM role to an AWS service (ec2), typically used for service access delegation. Then exploit PassRole Misconfiguration granting unauthorized access to sensitive resources.
- Objective: Demonstrate how a PassRole misconfiguration can grant unauthorized access.
- Steps:
- Allow user to pass IAM role to EC2.
- Exploit misconfiguration for unauthorized access.
- Access sensitive resources.
- Exploiting IAM AssumeRole Misconfiguration with Overly Permissive Role
- An overly permissive IAM role configuration can lead to privilege escalation by creating a role with administrative privileges and allow a user to assume this role.
- Objective: Show how overly permissive IAM roles can lead to privilege escalation.
- Steps:
- Create role with administrative privileges.
- Allow user to assume the role.
- Perform administrative actions.
- Differentiation between PassRole vs AssumeRole
Try at [killercoda.com](https://killercoda.com/cloudsecurity-scenario/)
CHINA’S GEO-ECONOMIC OUTREACH IN CENTRAL ASIAN COUNTRIES AND FUTURE PROSPECTjpsjournal1
The rivalry between prominent international actors for dominance over Central Asia's hydrocarbon
reserves and the ancient silk trade route, along with China's diplomatic endeavours in the area, has been
referred to as the "New Great Game." This research centres on the power struggle, considering
geopolitical, geostrategic, and geoeconomic variables. Topics including trade, political hegemony, oil
politics, and conventional and nontraditional security are all explored and explained by the researcher.
Using Mackinder's Heartland, Spykman Rimland, and Hegemonic Stability theories, examines China's role
in Central Asia. This study adheres to the empirical epistemological method and has taken care of
objectivity. This study analyze primary and secondary research documents critically to elaborate role of
china’s geo economic outreach in central Asian countries and its future prospect. China is thriving in trade,
pipeline politics, and winning states, according to this study, thanks to important instruments like the
Shanghai Cooperation Organisation and the Belt and Road Economic Initiative. According to this study,
China is seeing significant success in commerce, pipeline politics, and gaining influence on other
governments. This success may be attributed to the effective utilisation of key tools such as the Shanghai
Cooperation Organisation and the Belt and Road Economic Initiative.
Optimizing Gradle Builds - Gradle DPE Tour Berlin 2024Sinan KOZAK
Sinan from the Delivery Hero mobile infrastructure engineering team shares a deep dive into performance acceleration with Gradle build cache optimizations. Sinan shares their journey into solving complex build-cache problems that affect Gradle builds. By understanding the challenges and solutions found in our journey, we aim to demonstrate the possibilities for faster builds. The case study reveals how overlapping outputs and cache misconfigurations led to significant increases in build times, especially as the project scaled up with numerous modules using Paparazzi tests. The journey from diagnosing to defeating cache issues offers invaluable lessons on maintaining cache integrity without sacrificing functionality.
Software Engineering and Project Management - Introduction, Modeling Concepts...Prakhyath Rai
Introduction, Modeling Concepts and Class Modeling: What is Object orientation? What is OO development? OO Themes; Evidence for usefulness of OO development; OO modeling history. Modeling
as Design technique: Modeling, abstraction, The Three models. Class Modeling: Object and Class Concept, Link and associations concepts, Generalization and Inheritance, A sample class model, Navigation of class models, and UML diagrams
Building the Analysis Models: Requirement Analysis, Analysis Model Approaches, Data modeling Concepts, Object Oriented Analysis, Scenario-Based Modeling, Flow-Oriented Modeling, class Based Modeling, Creating a Behavioral Model.
Batteries -Introduction – Types of Batteries – discharging and charging of battery - characteristics of battery –battery rating- various tests on battery- – Primary battery: silver button cell- Secondary battery :Ni-Cd battery-modern battery: lithium ion battery-maintenance of batteries-choices of batteries for electric vehicle applications.
Fuel Cells: Introduction- importance and classification of fuel cells - description, principle, components, applications of fuel cells: H2-O2 fuel cell, alkaline fuel cell, molten carbonate fuel cell and direct methanol fuel cells.
The CBC machine is a common diagnostic tool used by doctors to measure a patient's red blood cell count, white blood cell count and platelet count. The machine uses a small sample of the patient's blood, which is then placed into special tubes and analyzed. The results of the analysis are then displayed on a screen for the doctor to review. The CBC machine is an important tool for diagnosing various conditions, such as anemia, infection and leukemia. It can also help to monitor a patient's response to treatment.