Mumbai University.
Mechanical Engineering
SEM III
Material Technology
Module 2.3
Creep:
Definition and significance of creep, Effect of temperature and creep on mechanical behaviours of materials, Creep testing and data presentation and analysis, Mechanism and types of creep, Analysis of classical creep curve and use of creep rate in designing of products for load-bearing applications, Creep Resistant materials
Main Features of Viscoelastic Behavior in MaterialsLuís Rita
Homework III - Biomaterials Science
Viscoelasticity is the property of materials that exhibit both elastic and viscous characteristics when undergoing deformation. Viscous materials: resist shear flow and strain linearly with time (Newtonian material) when a stress is applied. Elastic materials: strain when stretched and quickly return to their original state once the stress is removed.
IST - 4th Year - 2nd Semester - Biomedical Engineering.
This lecture constitutes an introduction to creep and to the creep response of aluminium and its alloys. It provides basic information on creep and its mechanisms; it gives a description of the more extensively used mathematical relations among creep variables (time, stress and temperature); it illustrates the creep response of pure Aluminium and of Al-Mg alloys; it provides a synthesis of the information available in the literature on the creep behaviour of a number of new alloys and composites in the form of a series of figures elaborated on the basis of the data reported in same sources. Basic knowledge of physics and chemistry and some familiarity with TALAT lectures 1201 through 1205 is assumed.
Mumbai University.
Mechanical Engineering
SEM III
Material Technology
Module 2.3
Creep:
Definition and significance of creep, Effect of temperature and creep on mechanical behaviours of materials, Creep testing and data presentation and analysis, Mechanism and types of creep, Analysis of classical creep curve and use of creep rate in designing of products for load-bearing applications, Creep Resistant materials
Main Features of Viscoelastic Behavior in MaterialsLuís Rita
Homework III - Biomaterials Science
Viscoelasticity is the property of materials that exhibit both elastic and viscous characteristics when undergoing deformation. Viscous materials: resist shear flow and strain linearly with time (Newtonian material) when a stress is applied. Elastic materials: strain when stretched and quickly return to their original state once the stress is removed.
IST - 4th Year - 2nd Semester - Biomedical Engineering.
This lecture constitutes an introduction to creep and to the creep response of aluminium and its alloys. It provides basic information on creep and its mechanisms; it gives a description of the more extensively used mathematical relations among creep variables (time, stress and temperature); it illustrates the creep response of pure Aluminium and of Al-Mg alloys; it provides a synthesis of the information available in the literature on the creep behaviour of a number of new alloys and composites in the form of a series of figures elaborated on the basis of the data reported in same sources. Basic knowledge of physics and chemistry and some familiarity with TALAT lectures 1201 through 1205 is assumed.
ION BEAMS' HYDRODYNAMIC APPROACH TO THE GENERATION OF SURFACE PATTERNSIAEME Publication
Amorphous solids can flow given the right timescale. In lead pipes or glaciers, solid flow can be seen in great detail, but it can also be manipulated by adding flaws. Ion Beam Sputtering (IBS) is a method in which ions with energies between 0.1 and 10 keV strike on a solid target, causing the formation of defects and their dynamics as well as degrading its surface and creating ordered nanostructures. Despite being technologically intriguing, a fundamental understanding of the nanopattern creation processes that take place under IBS of amorphizable targets has not been developed, with recent research on Si having mainly questioned knowledge collected over the last two decades. In the past, a number of interfacial equations have been presented to explain these phenomena. Typically, these equations involve nonsystematic addition of various contributions from surface diffusion, ion sputtering, mass redistribution, etc. In order to create a broad framework into which various mechanisms (such as viscous flow, stress, diffusion, or sputtering) can be added, under general physical conservation rules, we here take advantage of the general idea of solids flowing due to ion impacts. This approach enables a systematic evaluation of the relevance and interaction of several physical factors influencing surface pattern generation by IBS as opposed to the formulation of phenomenological interfacial equations.
Adhesion is linked with surface forces like capillary pressure and is thus detrimental at the
nanoscale where body forces are negligible. It can lead to instant failure during fabrication and
operation but it can also lead to overtime failure because of induced friction and wear. However,
when it is possible, coating a device with hydrophobic materials reduces drastically that mechanism.
Understanding how adhesion works is crucial to design new systems and to enable new
technologies. Two models (JKR and DMT) are studied in this paper and model adhesion in different
cases. Photolithography and particularly the release step must be carefully designed to prevent
contamination and stiction. Materials must be chosen and designed wisely to prevent adhesion
failure during operation but lubricants can be used to reduce its impact as well as the impact of
friction and wear.
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.
Physical Characterization of a Method for Production of High Stability Suspen...Editor IJCATR
Suspensions/Dispersions are encountered in a wide range of
applications, e.g., liquid abrasive cleaners, ceramics, medicines,
inks, paints….etc. In most cases it is necessary to keep the
suspension stable for the product lifetime. A new modified
differential sedimentation measuring system is suggested and used
to identify physical parameters affecting the sedimentation in
suspensions. The technique is discussed in details. It is found that
particle sizes as well as viscosity of continuous phase are the most
important factors governing the stability of a suspension. Empirical
relations are extracted to quantitatively describe the weight effect of
each factor. The modified measuring system shows good accuracy
enough to detect fluctuations in concentration of suspended
particles due to their Brownian diffusion, as well as the particles
concentrations in the stable suspension. This study confirmed the
fact that particles diameters measured by Zetasizer are much
greater than those measured by the transmission electron
microscope. This study presents a proposal for new technique for
particle size separation based on the differential sedimentation in
viscose fluids. This new method is a differential viscosity column.
The proposed size separation technique may help to separate
engineered nano-particles with higher resolution
Seminar Report on Brittle Fracture of ShipsVISHAL SHARMA
This study investigates the sinking of the Titanic from the theory of Brittle Fracture and
Engineering Failures. This study offers a subjectivist perspective of mental inertia to
understand the Titanic Disaster. Specifically, this study argue that the fall of the Titanic was
mainly due to Brittle Fracture of Rivets and the Hull Steel. Metallurgical and Mechanical
Analysis were performed on steel and rivet samples recovered from the wreck of the RMS
Titanic. It is found that the steel possessed a ductile-to-brittle transition temperature that was
very high with respect to the service temperature, making the material very brittle at ice-water
temperatures. This had been attributed to both chemical and microstructural factors. It is also
been found that the wrought iron rivets used in the construction of Titanic contained an elevated
amount of incorporated slag, and that the orientation of the slag within the rivets may hold an
explanation for how the ship accumulated damage during its encounter with the iceberg.
Keywords- Brittle fracture, Rivets, Hull Steel, Metallurgical Failure, Titanic Disaster.
Tribology assignment regarding the fundamentals of friction, containing: Introduction
Rules of Friction
Exceptions
Mechanism
Cases of Friction
Friction of common materials
& Conclusion
IOSR Journal of Mathematics(IOSR-JM) is an open access international journal that provides rapid publication (within a month) of articles in all areas of mathemetics and its applications. The journal welcomes publications of high quality papers on theoretical developments and practical applications in mathematics. Original research papers, state-of-the-art reviews, and high quality technical notes are invited for publications.
Gravitational Instability in a Ferromagnetic Fluid Saturated Porous Medium wi...IOSR Journals
The problem of Rayleigh-Bénard convection in a ferromagnetic fluid saturated porous medium with
the Maxwell-Cattaneo law is studied by the method of small perturbation. Modified Darcy-Brinkman model is
used to describe the fluid motion. The horizontal porous layer is cooled from the upper boundary, while an
isothermal boundary condition is imposed at the lower boundary. The non-classical Maxwell-Cattaneo heat flux
law involves a wave type heat transport and does not suffer from the physically unacceptable drawback of
infinite heat propagation speed. The resulting eigenvalue problem is solved exactly for simplified boundary
conditions and the thresholds for the marginal stability are determined. Some of the known cases are derived as
special cases. The influence of porous, magnetic, and non-magnetic parameters on the onset of ferroconvection
has been analyzed. It is found that the Bénard problem for a Maxwell-Cattaneo ferromagnetic fluid is always
less stable than the classical ferroconvection problem. It is shown that the destabilizing influence of the
Cattaneo number is not attenuated by that of magnetic forces and vice versa, and that the aspect ratio of the
convection cells changes when the parameters involved in the study vary with the porous structure bringing out
considerable influence.
Magneto-Thermosolutal Convection in Maxwellian Dusty Viscoelastic Fluid throu...IJERA Editor
Thermosolutal convection in Maxwellian viscoelastic fluid under the simultaneous effects of uniform vertical magnetic field and suspended particles through porous medium is mathematically investigated. A sufficient condition for the invalidity of the ‘principle of exchange of stabilities’ is derived, in the context, which states that the exchange principle is not valid provided the thermal Rayleigh number R , solutal Rayleigh number S R , the medium permeability 1 P and the suspended particles parameter B are restricted by the inequality 1 2 1 S R R BP .
Dislocation and twin substructure evolution during strain hardening of an Fe–22 wt.% Mn–0.6 wt.% C TWIP steel observed by electron channeling contrast imaging
ION BEAMS' HYDRODYNAMIC APPROACH TO THE GENERATION OF SURFACE PATTERNSIAEME Publication
Amorphous solids can flow given the right timescale. In lead pipes or glaciers, solid flow can be seen in great detail, but it can also be manipulated by adding flaws. Ion Beam Sputtering (IBS) is a method in which ions with energies between 0.1 and 10 keV strike on a solid target, causing the formation of defects and their dynamics as well as degrading its surface and creating ordered nanostructures. Despite being technologically intriguing, a fundamental understanding of the nanopattern creation processes that take place under IBS of amorphizable targets has not been developed, with recent research on Si having mainly questioned knowledge collected over the last two decades. In the past, a number of interfacial equations have been presented to explain these phenomena. Typically, these equations involve nonsystematic addition of various contributions from surface diffusion, ion sputtering, mass redistribution, etc. In order to create a broad framework into which various mechanisms (such as viscous flow, stress, diffusion, or sputtering) can be added, under general physical conservation rules, we here take advantage of the general idea of solids flowing due to ion impacts. This approach enables a systematic evaluation of the relevance and interaction of several physical factors influencing surface pattern generation by IBS as opposed to the formulation of phenomenological interfacial equations.
Adhesion is linked with surface forces like capillary pressure and is thus detrimental at the
nanoscale where body forces are negligible. It can lead to instant failure during fabrication and
operation but it can also lead to overtime failure because of induced friction and wear. However,
when it is possible, coating a device with hydrophobic materials reduces drastically that mechanism.
Understanding how adhesion works is crucial to design new systems and to enable new
technologies. Two models (JKR and DMT) are studied in this paper and model adhesion in different
cases. Photolithography and particularly the release step must be carefully designed to prevent
contamination and stiction. Materials must be chosen and designed wisely to prevent adhesion
failure during operation but lubricants can be used to reduce its impact as well as the impact of
friction and wear.
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.
Physical Characterization of a Method for Production of High Stability Suspen...Editor IJCATR
Suspensions/Dispersions are encountered in a wide range of
applications, e.g., liquid abrasive cleaners, ceramics, medicines,
inks, paints….etc. In most cases it is necessary to keep the
suspension stable for the product lifetime. A new modified
differential sedimentation measuring system is suggested and used
to identify physical parameters affecting the sedimentation in
suspensions. The technique is discussed in details. It is found that
particle sizes as well as viscosity of continuous phase are the most
important factors governing the stability of a suspension. Empirical
relations are extracted to quantitatively describe the weight effect of
each factor. The modified measuring system shows good accuracy
enough to detect fluctuations in concentration of suspended
particles due to their Brownian diffusion, as well as the particles
concentrations in the stable suspension. This study confirmed the
fact that particles diameters measured by Zetasizer are much
greater than those measured by the transmission electron
microscope. This study presents a proposal for new technique for
particle size separation based on the differential sedimentation in
viscose fluids. This new method is a differential viscosity column.
The proposed size separation technique may help to separate
engineered nano-particles with higher resolution
Seminar Report on Brittle Fracture of ShipsVISHAL SHARMA
This study investigates the sinking of the Titanic from the theory of Brittle Fracture and
Engineering Failures. This study offers a subjectivist perspective of mental inertia to
understand the Titanic Disaster. Specifically, this study argue that the fall of the Titanic was
mainly due to Brittle Fracture of Rivets and the Hull Steel. Metallurgical and Mechanical
Analysis were performed on steel and rivet samples recovered from the wreck of the RMS
Titanic. It is found that the steel possessed a ductile-to-brittle transition temperature that was
very high with respect to the service temperature, making the material very brittle at ice-water
temperatures. This had been attributed to both chemical and microstructural factors. It is also
been found that the wrought iron rivets used in the construction of Titanic contained an elevated
amount of incorporated slag, and that the orientation of the slag within the rivets may hold an
explanation for how the ship accumulated damage during its encounter with the iceberg.
Keywords- Brittle fracture, Rivets, Hull Steel, Metallurgical Failure, Titanic Disaster.
Tribology assignment regarding the fundamentals of friction, containing: Introduction
Rules of Friction
Exceptions
Mechanism
Cases of Friction
Friction of common materials
& Conclusion
IOSR Journal of Mathematics(IOSR-JM) is an open access international journal that provides rapid publication (within a month) of articles in all areas of mathemetics and its applications. The journal welcomes publications of high quality papers on theoretical developments and practical applications in mathematics. Original research papers, state-of-the-art reviews, and high quality technical notes are invited for publications.
Gravitational Instability in a Ferromagnetic Fluid Saturated Porous Medium wi...IOSR Journals
The problem of Rayleigh-Bénard convection in a ferromagnetic fluid saturated porous medium with
the Maxwell-Cattaneo law is studied by the method of small perturbation. Modified Darcy-Brinkman model is
used to describe the fluid motion. The horizontal porous layer is cooled from the upper boundary, while an
isothermal boundary condition is imposed at the lower boundary. The non-classical Maxwell-Cattaneo heat flux
law involves a wave type heat transport and does not suffer from the physically unacceptable drawback of
infinite heat propagation speed. The resulting eigenvalue problem is solved exactly for simplified boundary
conditions and the thresholds for the marginal stability are determined. Some of the known cases are derived as
special cases. The influence of porous, magnetic, and non-magnetic parameters on the onset of ferroconvection
has been analyzed. It is found that the Bénard problem for a Maxwell-Cattaneo ferromagnetic fluid is always
less stable than the classical ferroconvection problem. It is shown that the destabilizing influence of the
Cattaneo number is not attenuated by that of magnetic forces and vice versa, and that the aspect ratio of the
convection cells changes when the parameters involved in the study vary with the porous structure bringing out
considerable influence.
Magneto-Thermosolutal Convection in Maxwellian Dusty Viscoelastic Fluid throu...IJERA Editor
Thermosolutal convection in Maxwellian viscoelastic fluid under the simultaneous effects of uniform vertical magnetic field and suspended particles through porous medium is mathematically investigated. A sufficient condition for the invalidity of the ‘principle of exchange of stabilities’ is derived, in the context, which states that the exchange principle is not valid provided the thermal Rayleigh number R , solutal Rayleigh number S R , the medium permeability 1 P and the suspended particles parameter B are restricted by the inequality 1 2 1 S R R BP .
Dislocation and twin substructure evolution during strain hardening of an Fe–22 wt.% Mn–0.6 wt.% C TWIP steel observed by electron channeling contrast imaging
Similar to Unstable Plastic Flow in the Industrial Al-2, 5%Mg Alloy, Effect of Annealing Process (20)
Palestine last event orientationfvgnh .pptxRaedMohamed3
An EFL lesson about the current events in Palestine. It is intended to be for intermediate students who wish to increase their listening skills through a short lesson in power point.
The French Revolution, which began in 1789, was a period of radical social and political upheaval in France. It marked the decline of absolute monarchies, the rise of secular and democratic republics, and the eventual rise of Napoleon Bonaparte. This revolutionary period is crucial in understanding the transition from feudalism to modernity in Europe.
For more information, visit-www.vavaclasses.com
How to Split Bills in the Odoo 17 POS ModuleCeline George
Bills have a main role in point of sale procedure. It will help to track sales, handling payments and giving receipts to customers. Bill splitting also has an important role in POS. For example, If some friends come together for dinner and if they want to divide the bill then it is possible by POS bill splitting. This slide will show how to split bills in odoo 17 POS.
Model Attribute Check Company Auto PropertyCeline George
In Odoo, the multi-company feature allows you to manage multiple companies within a single Odoo database instance. Each company can have its own configurations while still sharing common resources such as products, customers, and suppliers.
Operation “Blue Star” is the only event in the history of Independent India where the state went into war with its own people. Even after about 40 years it is not clear if it was culmination of states anger over people of the region, a political game of power or start of dictatorial chapter in the democratic setup.
The people of Punjab felt alienated from main stream due to denial of their just demands during a long democratic struggle since independence. As it happen all over the word, it led to militant struggle with great loss of lives of military, police and civilian personnel. Killing of Indira Gandhi and massacre of innocent Sikhs in Delhi and other India cities was also associated with this movement.
Instructions for Submissions thorugh G- Classroom.pptxJheel Barad
This presentation provides a briefing on how to upload submissions and documents in Google Classroom. It was prepared as part of an orientation for new Sainik School in-service teacher trainees. As a training officer, my goal is to ensure that you are comfortable and proficient with this essential tool for managing assignments and fostering student engagement.
The Indian economy is classified into different sectors to simplify the analysis and understanding of economic activities. For Class 10, it's essential to grasp the sectors of the Indian economy, understand their characteristics, and recognize their importance. This guide will provide detailed notes on the Sectors of the Indian Economy Class 10, using specific long-tail keywords to enhance comprehension.
For more information, visit-www.vavaclasses.com
Students, digital devices and success - Andreas Schleicher - 27 May 2024..pptxEduSkills OECD
Andreas Schleicher presents at the OECD webinar ‘Digital devices in schools: detrimental distraction or secret to success?’ on 27 May 2024. The presentation was based on findings from PISA 2022 results and the webinar helped launch the PISA in Focus ‘Managing screen time: How to protect and equip students against distraction’ https://www.oecd-ilibrary.org/education/managing-screen-time_7c225af4-en and the OECD Education Policy Perspective ‘Students, digital devices and success’ can be found here - https://oe.cd/il/5yV
GIÁO ÁN DẠY THÊM (KẾ HOẠCH BÀI BUỔI 2) - TIẾNG ANH 8 GLOBAL SUCCESS (2 CỘT) N...
Unstable Plastic Flow in the Industrial Al-2, 5%Mg Alloy, Effect of Annealing Process
1. Abstract of Applied Sciences and Engineering, 2016, Vol.9
DOI: 10.18488/journal.1001/2016.9/1001.9
9th
International Scientific Conference on Applied
Sciences and Engineering
6-7 June 2016
Nippon Hotel, İstanbul-Turkey
Conference Website: www.scihost.org
19
Paper ID: 19/16/ 9
th
ISCASE
Unstable Plastic Flow in the Industrial Al-2, 5%Mg Alloy,
Effect of Annealing Process
Chibane Nouara --- Ait-Amokhtar Hakim
Abstract
At the microscopic scale, a plastically deformed material constitutes a nonlinear system with
a large number of parameters related to the presence of defects (dislocations, impurities,
precipitates, etc.). These microscopic heterogeneities lead, in general, to homogeneous
macroscopic plastic flow in a large interval of deformation. Thus the flow stress increases
with the applied strain rate. However, in certain conditions of temperature, strain rate and
deformation, interaction between dislocations and their transport can lead to an instable
plastic flow, in particular in face –centered cubic (fcc) materials where dislocations present
a high mobility. Thus, a uniform plastic flow regime gives way to a localized deformation
mode. In such conditions, the complexity and the non linearity of the microscopic parameters
generate instabilities of plastic flow; localizations appear on a macroscopic scale by the
spontaneous formation of heterogeneities and defects, sometimes regular and propagatifs,
which can be observed on the surface of the deformed material. A commonly observed
heterogeneous plastic flow is the Portevin-Le Chatelier (PLC) phenomenon. It is due to
dynamic strain aging (DSA), i.e., a dynamic interaction between solute atoms and mobile
dislocations. The solute atoms diffuse to and pin mobile dislocations during their temporary
arrest at local obstacles (forest dislocations, precipitates, etc.). Instabilities arise when the
waiting time of dislocations at obstacles is of the order of the diffusion time of the solute
atoms.The repeated breakaway of dislocations from the solute clouds reduces the strain rate
sensitivity (SRS) of the flow stress which becomes negative. Therefore, the strain localizes
into narrow deformation bands and gives rise to serrated stress-strain curve at constant
applied strain rate. The purpose of the present work is focused on the analysis of the
temporal aspects of the PLC effect in the Al-2.5%Mg alloy. We have investigated the
Portevin “Le Chatelier characteristics at room temperature in annealed and cold “rolled Al-
2.5%Mg alloys. We have shown that the heat treatment affects significantly the jerky flow,
namely, the range of instability, the critical strain for the onset of serrations and the ductility
of the alloy. We interpret our results in accordance with dynamic strain aging mechanisms.
Keywords: Plastic Flow, Annealing Proces
