The Effect of Substrate on the Microstructure and Mechanical Behavior of Eutectic Indium-Tin

1993 ◽  
Vol 323 ◽  
Author(s):  
J. L. Freer Goldstein ◽  
J. W. Morris
Keyword(s):  
Mechanical Behavior ◽  
Mechanical Testing ◽  
Creep Deformation ◽  
Activation Energies ◽  
Behavior Changes ◽  
Stress Strain ◽  
Cu Substrates ◽  
Different Shapes

AbstractThis study was conducted in order to determine and understand the effect of substrate on eutectic In-Sn. Samples for mechanical testing were produced with either bare Cu or Ni on Cu substrates. Both the microstructure and the mechanical behavior are strongly dependent on substrate, with In-Sn on Cu having a non-uniform and irregular microstructure and In-Sn on Ni having a uniform, normal colony-based eutectic. Deformation is more uniform in the In-Sn on Ni, while it is concentrated along the length of the joint in the In-Sn on Cu. This is reflected in the different shapes of stress-strain curves between In-Sn on Cu and In-Sn on Ni. The stress exponents and activation energies for creep also vary with substrate. Creep deformation is governed by the In-rich γ phase for In-Sn on Cu and by the Sn-rich y phase for In-Sn on Ni. If In-Sn on Ni samples are aged, the microstructure coarsens and the mechanical behavior changes to resemble that of the as-cast In-Sn on Cu.

Mechanical Characterization of Assemblies Bonded With Pressure-Sensitive Adhesives (PSAs)

2015 ◽  
Author(s):  
Hao Huang ◽  
Abhijit Dasgupta ◽  
Ehsan Mirbagheri ◽  
Srini Boddapati
Keyword(s):  
Mechanical Behavior ◽  
Failure Modes ◽  
Mechanical Characterization ◽  
Bonding Temperature ◽  
Process Conditions ◽  
Second Phase ◽  
Loading Conditions ◽  
Stress Strain ◽  
Strain Behavior ◽  
Pressure Sensitive

The focus of this paper is on the stress-strain behavior and creep response of a pressure-sensitive adhesive (PSA) with and without carrier layers. This study consists of two phases. The first phase focuses on understanding of the effects of fabrication profiles, including bonding pressure, bonding temperature, bonding time, and aging time, on the PSA joint strength. This part of the study is used to identify an acceptable bonding and aging conditions for manufacturing a robust PSA bonded assembly. Specimens fabricated with this selected set of bonding process conditions are then used for mechanical characterization. The second phase focuses on the assembly’s mechanical behavior (stress-strain behavior and the creep curves) under different loading conditions, including loading stress, loading rate, and loading temperature. The mechanical behavior of PSA bonded assemblies is affected not only by the loading conditions, but also by the assembly architecture. The mechanical behaviors and failure modes of PSAs with and without carrier layers are compared. The reasons for these differences are also discussed.

Plasticity of MoSi2 Below 900°C

1993 ◽  
Vol 322 ◽  
Author(s):  
H. Chang ◽  
R. Gibala
Keyword(s):  
Dislocation Density ◽  
Mechanical Behavior ◽  
Yield Point ◽  
Stress Strain ◽  
Temperature Range ◽  
Dislocation Plasticity

AbstractThe mechanical behavior of polycrystalline MoSi2 tested in compression at temperatures from 750°C to 950°C has been investigated. This material can be deformed to several percent strain without fracture at temperatures as low as 900°C. This same material prestrained at 1300°C and subsequently tested at lower temperatures can be deformed to substantial strain at 800°C, and even exhibits modest plasticity at 750°C. Both prestrained and unprestrained materials exhibit microcracking combined with dislocation substructures containing high densities of dislocations. Unprestrained MoSi2 exhibits a yield point in this temperature range which does not exist when it is prestrained. The stress-strain curves of the prestrained material in this temperature range are similar qualitatively to those of the unprestrained material at 1100°C and above. These observations suggest that at these temperatures MoSi2 is a dislocation density limited material which can deform by dislocation plasticity processes if a sufficient dislocation density is available.

Influence of Orthotropy on the Stress–Strain State of Quadrangular Plates of Different Shapes

2019 ◽  
Vol 55 (2) ◽  
pp. 199-210 ◽  
Author(s):  
A. Ya. Grigorenko ◽  
S. A. Pankrat’ev ◽  
S. N. Yaremchenko
Keyword(s):  
Strain State ◽  
Stress Strain ◽  
Stress Strain State ◽  
Different Shapes

scholarly journals Prediction of Stress–Strain Curves Based on Hydric Non-Destructive Tests on Sandstones

Materials ◽  
2019 ◽  
Vol 12 (20) ◽  
pp. 3366 ◽  
Author(s):  
Marco Ludovico-Marques ◽  
Carlos Chastre
Keyword(s):  
Physical Properties ◽  
Mechanical Behavior ◽  
Water Absorption ◽  
Analytical Model ◽  
Strain Curve ◽  
Low Pressure ◽  
Design Parameters ◽  
Compression Tests ◽  
Stress Strain ◽  
Non Destructive

The study of the mechanical behavior of building stones is traditionally supported by destructive compression tests carried out on representative specimens. However, in order to respect the monuments’ integrity, the study of the mechanical behavior of stones can be based mostly on physical properties obtained from non-destructive tests (NDT). For this study, a simple and cheap NDT—water absorption under low pressure—was used to carry out fast surveys and to predict the most important design parameters of loadbearing masonry, among which are the compressive strength, strain at failure, and even elastic modulus on monument blocks. The paper presents the results of the experimental work conducted to obtain the physical properties and stress–strain curves of the sandstones tested. Supported by these results, it was possible to correlate the various parameters and develop an analytical model that predicts the stress–strain curve of the sandstones based on water absorption under low pressure tests. A good agreement is observed between the analytical model and the experimental tests.

Derivation of Polycrystal Creep Properties From the Creep Data of Single Crystals

1977 ◽  
Vol 44 (1) ◽  
pp. 73-78 ◽  
Author(s):  
T. H. Lin ◽  
C. L. Yu ◽  
G. J. Weng
Keyword(s):  
Single Crystals ◽  
Creep Deformation ◽  
Tensile Loading ◽  
Present Theory ◽  
Sole Source ◽  
Stress And Strain ◽  
Creep Data ◽  
Stress Strain ◽  
Macroscopic Stress ◽  
Additional Constant

A method developed for calculating the polycrystal stress-strain-time relation from the creep data of single crystals is shown. Slip is considered to be the sole source of creep deformation. This method satisfies, throughout the aggregate, both the condition of equilibrium and that of continuity of displacement as well as the creep characteristics of single crystals. A very large three-dimensional region is assumed to be filled with innumerable identical cubic blocks, each of which consists of 64 cube-shaped crystals of different orientations. This region is assumed to be embedded in an infinite elastic isotropic medium. This infinite medium is subject to a uniform loading. The average stress and strain of a cubic block at the center of the region is taken to represent the macroscopic stress and strain of the polycrystal. This method is self-consistent and considers the heterogeneous interaction effect of the creep deformation of all slid crystals. The macroscopic stress-strain-time relations of the polycrystal were calculated for three tensile loadings, one radial loading, and two nonradial loadings of combined tension and torsion. The numerical results given by the present theory agree well with those predicted by the so-called “Mechanical Equation of State.” The creep strain components calculated by the present theory for the case of a constant tensile loading followed by an additional constant tensile loading are found to be considerably higher than those predicted by von Mises and Tresca’s theories. These results agree well qualitatively with experimental results.

Mechanical Properties in Small Dimensions

MRS Bulletin ◽  
2002 ◽  
Vol 27 (1) ◽  
pp. 12-17 ◽  
Author(s):  
Richard P. Vinci ◽  
Shefford P. Baker
Keyword(s):  
Thin Film ◽  
Mechanical Properties ◽  
Mechanical Behavior ◽  
Significant Role ◽  
Creep Deformation ◽  
Film Growth ◽  
Thin Film Growth ◽  
Length Scale ◽  
Deformation And Fracture ◽  
Anelastic Behavior

AbstractThis brief article describes the content of the January 2002 issue of MRS Bulletin focusing on Mechanical Properties in Small Dimensions. Articles discuss the current understanding ofstressevolution during thin-film growth, elastic and anelastic behavior, dislocation-mediated plasticity, creep deformation, and fracture. Emphasis is placed on explaining the mechanisms that underlie thewell-known fact that length scale can play a significant role in mechanical behavior.

Microstructural Characteristics of Polyurea and Polyurethanexerogels for Concrete Confinement with FRP System

2013 ◽  
Vol 742 ◽  
pp. 237-242 ◽  
Author(s):  
Mostafa Fakharifar ◽  
Zhi Bin Lin ◽  
Cheng Lin Wu ◽  
Shruti Mahadik-Khanolkar ◽  
Nicholas Leventis ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Pilot Study ◽  
Mechanical Behavior ◽  
Confined Concrete ◽  
Stress Strain ◽  
Microstructural Characteristics ◽  
Concrete Confinement ◽  
Energy Absorbing

Due to their exceptional mechanical properties,xerogels attract increasing attention forstructural applications. In this study, the mechanical behavior of two types of polymeric xerogelsis investigated. The excellent energy-absorbing capability of those xerogelsis demonstrated by their stress-strain relations with respect to their microstructure determined withscanning electron microscopy (SEM). A pilot study on the effects of xerogellayers in an FRP system for concrete confinementis conducted.Test results clearly indicatedthat the proposed multi-layer systemcan significantly increase the ductility of confined concrete.

Sign in / Sign up

Export Citation Format

Share Document