Mechanical Properties and Constitutive Model Applied to the High-Speed Impact of Aluminum Foam That Considers Its Meso-Structural Parameters

In this work, quasistatic mechanical compression experiments were used to study the stress–strain relationship of aluminum foam, and the mechanism of the compressive deformation of aluminum foam under quasistatic compression conditions is discussed based on the experimental observations. Since the interactions among cells of the aluminum foam and differences in compressive strength among cells substantially impacted the mechanical properties of the material, the cellular structural parameters, namely the cell size and cell wall thickness, were defined. Along with the mechanism of deformation of a single cell, the influence of structural parameters on the micro failure mechanism and the stress–strain relationship of the aluminum foam material was analyzed. In combination with the factors influencing the mechanical properties of the aluminum foam, a mechanical constitutive model of aluminum foam suitable for multi-density and multi-impact environments that considers cellular structure density was established to predict the complete stress–strain relationship of aluminum foam under a high strain rate. The coupling function of strain rate and temperature in the original model was verified and the parameters were determined by the compression experiments under different strain rates and different temperatures.

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Dynamic Constitutive Model of Ultra-High Molecular Weight Polyethylene (UHMWPE): Considering the Temperature and Strain Rate Effects

Polymers ◽

10.3390/polym12071561 ◽

2020 ◽

Vol 12 (7) ◽

pp. 1561 ◽

Cited By ~ 1

Author(s):

Kebin Zhang ◽

Wenbin Li ◽

Yu Zheng ◽

Wenjin Yao ◽

Changfang Zhao

Keyword(s):

Mechanical Properties ◽

Constitutive Model ◽

Strain Rate ◽

Split Hopkinson Pressure Bar ◽

Plastic Material ◽

Strain Rates ◽

Hopkinson Pressure Bar ◽

Ballistic Performance ◽

Stress Strain ◽

Different Temperatures

The temperature and strain rate significantly affect the ballistic performance of UHMWPE, but the deformation of UHMWPE under thermo-mechanical coupling has been rarely studied. To investigate the influences of the temperature and the strain rate on the mechanical properties of UHMWPE, a Split Hopkinson Pressure Bar (SHPB) apparatus was used to conduct uniaxial compression experiments on UHMWPE. The stress–strain curves of UHMWPE were obtained at temperatures of 20–100 °C and strain rates of 1300–4300 s−1. Based on the experimental results, the UHMWPE belongs to viscoelastic–plastic material, and a hardening effect occurs once UHMWPE enters the plastic zone. By comparing the stress–strain curves at different temperatures and strain rates, it was found that UHMWPE exhibits strain rate strengthening and temperature softening effects. By modifying the Sherwood–Frost model, a constitutive model was established to describe the dynamic mechanical properties of UHMWPE at different temperatures. The results calculated using the constitutive model were in good agreement with the experimental data. This study provides a reference for the design of UHMWPE as a ballistic-resistant material.

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A Statistical Constitutive Model for the Strength of Brittle Fiber at Different Strain Rates

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.152-153.1213 ◽

2010 ◽

Vol 152-153 ◽

pp. 1213-1216

Author(s):

Wen Huang ◽

Zhong Wei Huang

Keyword(s):

Constitutive Model ◽

Strain Rate ◽

Tensile Tests ◽

Fiber Bundles ◽

Strain Rates ◽

Stress Strain ◽

Sic Fiber ◽

Brittle Fiber ◽

Strain Relationship ◽

Relationship Of

A statistical constitutive model, which takes account the effect of strain rate, was presented to describe the stress-strain relationship of brittle fiber bundles. To verify its reliability, tensile tests on two kinds of brittle fibers: glass fiber and SiC fiber, were carried out at different strain rates, and the stress-strain curves were obtained. It was found that the modulus E, the strength and the fracture strain of these fiber bundles all increase with increasing strain rate. The simulated stress-strain curves, derived from the constitutive model, fit the tested results well, which indicates that the model is valid and reliable.

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Damage constitutive model of stratified cemented backfill based on coupling macroscopic and mesoscopic deformations

E3S Web of Conferences ◽

10.1051/e3sconf/202019405024 ◽

2020 ◽

Vol 194 ◽

pp. 05024

Author(s):

Yanan Tang ◽

Weidong Song ◽

Jianxin Fu

Keyword(s):

Mechanical Properties ◽

Constitutive Model ◽

Compressive Load ◽

Strain Curve ◽

Strength Distribution ◽

Stress Strain ◽

Strain Relationship ◽

Damage Constitutive Model ◽

Stratified Structure ◽

Relationship Of

The mechanical properties and stress-strain relationship of cemented backfills with different stratified structure have a direct effect on the mining-filling cycle and the mining of adjacent pillars. To obtain the stress-strain evolution curves, the uniaxial compressive strength tests were performed on backfills with stratified numbers of 0, 1, 2 and 3. The deformation of stratified backfill under the compressive load is regarded as a compound of closed deformation of the macroscopic stratified structure and elastic deformation of material. The damage constitutive model of cemented backfills with different stratified structure are established by considering the influence of compacted section. Comparative analysis reveals that the calculated curve based on the established sectional damage constitutive model conforms well to the trial curve. The maximum closed strain of the structural plane has a more significant effect on the mechanical properties of backfill. In the Weibull distribution, with the increase of the parameter m, the peak strength of backfill gradually increases and then reaches to a certain value, and the stress-strain curve gradually becomes steeper, which shows that m is a reflection of the concentration level of micro-unit strength distribution in the backfill..

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Mechanical Behavior Simulation of PMMA for Nano Imprint Lithography Using Molecular Dynamics

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.345-346.979 ◽

2007 ◽

Vol 345-346 ◽

pp. 979-982 ◽

Cited By ~ 1

Author(s):

Jung Yup Kim ◽

Jae Hyun Kim ◽

Byung Ik Choi

Keyword(s):

Mechanical Properties ◽

Strain Rate ◽

Mechanical Strain ◽

Process Condition ◽

Imprint Lithography ◽

Stress Strain ◽

Behavior Simulation ◽

Strain Relationship ◽

Relationship Of ◽

Nano Imprint

NIL(Nano Imprint Lithography) is one of the most promising lithography techniques. There are many variants of NIL, and two major techniques of them are thermal NIL and UV NIL. Here, we focus ourselves on the thermal NIL. During the thermal NIL, the polymeric patterns experience large mechanical strain and high temperature, and this often leads to malformation of polymeric patterns. So it is needed to improve the pattern fidelity and contrast, and these are believed to be closely related to the process condition and mechanical properties. In thermal NIL, PMMA is widely used and chosen as target polymer. Generally, mechanical properties in nano scale are really hard to acquire. In this study, we estimate the mechanical properties of PMMA by molecular dynamic simulation. These properties will be used as input of continuum simulation. We will estimate stress-strain relationship of PMMA. This stress-strain relationship depends on strain rate and temperature. So we will study about strain rate and temperature effect.

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Study on Dynamic Mechanical Properties and Constitutive Model Construction of TC18 Titanium Alloy

Metals ◽

10.3390/met10010044 ◽

2019 ◽

Vol 10 (1) ◽

pp. 44 ◽

Cited By ~ 2

Author(s):

Changming Zhang ◽

Anle Mu ◽

Yun Wang ◽

Hui Zhang

Keyword(s):

Mechanical Properties ◽

Titanium Alloy ◽

Flow Stress ◽

Yield Strength ◽

Constitutive Model ◽

Testing Machine ◽

Dynamic Mechanical Properties ◽

Stress Strain ◽

Dynamic Mechanical ◽

Different Temperatures

In order to investigate the static and dynamic mechanical properties of TC18 titanium alloy, the quasi-static stress–strain curve of TC18 titanium alloy under room temperature was obtained by DNS 100 electronic universal testing machine (Changchun Institute of Mechanical Science Co., Ltd., Changchun, China). Meanwhile, the flow stress–strain curves under different temperatures and strain rates are analyzed by split Hopkinson pressure bar (SHPB) device with synchronous assembly system. On the basis of the two experimental data, the JC constitutive model under the combined action of high temperature and impact load is established using the linear least squares method. The results show the following: the yield strength and flow stress of TC18 titanium alloy increase slowly with the increase of the strain rate, and the strain value corresponding to the yield strength is reduced. With the increase of strain, the flow stress increases at first and then decreases at different temperatures. The strain value corresponding to the transition point rises with the temperature increase, and the corresponding stress value remains basically unchanged. With the increase of experimental temperature, the flow stress shows a downward trend, and the JC constitutive model can predict the plastic flow stress well.

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Effect of strain rate on the stress-strain relationship of tensile specimens of type PN-1 binder

Soviet Applied Mechanics ◽

10.1007/bf00882260 ◽

1972 ◽

Vol 8 (11) ◽

pp. 1213-1218

Author(s):

P. G. Shishkin

Keyword(s):

Strain Rate ◽

Stress Strain ◽

Strain Relationship ◽

Relationship Of

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Effect Analysis of Temperature on the Rubber Material Stress-Strain Relationship

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.977.116 ◽

2014 ◽

Vol 977 ◽

pp. 116-119 ◽

Cited By ~ 1

Author(s):

Yu Liang Yang ◽

Liang Qiao ◽

Cong Wang ◽

Fei Lu ◽

Xiao Hui Kang

Keyword(s):

Environmental Temperature ◽

Testing Machine ◽

Test Results ◽

Stress Strain ◽

Rubber Material ◽

Effect Analysis ◽

Universal Testing ◽

Different Temperatures ◽

Strain Relationship ◽

Relationship Of

For the effect of environmental temperature on the rubber material stress-strain relationships, rubber tensile specimens, compression specimens and shear specimens were made. Through the electronic universal testing machine Instron 5500R, the stress-strain curves of three kinds of specimens at different temperatures were obtained. The test results showed that the stress-strain relationship of rubber material was typically nonlinear. As the temperature increased, the elastic modulus of rubber material decreased.

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Experimental Research on the Stress - Strain Curve of Regional Confined Concrete under Single Axial Press

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.584-586.1289 ◽

2014 ◽

Vol 584-586 ◽

pp. 1289-1292

Author(s):

Guo Liang Zhu

Keyword(s):

Mechanical Properties ◽

Theoretical Analysis ◽

Constitutive Model ◽

Theoretical Basis ◽

Strain Curve ◽

Confined Concrete ◽

Constitutive Relationship ◽

Stress Strain Curve ◽

Stress Strain ◽

Relationship Of

Regional confined concrete is base on confined concrete. It is the theory and application of a new attempt and development on confined concrete. To apply it to the actual project, we need to research mechanical properties and establish constitutive relationship of regional confined concrete. According to the research, we had carried on a series of tests, founded the stress-strain constitutive model of regional confined concrete under single axial press. The accuracy of theoretical analysis were more fully verified , and a theoretical basis for the application was provided.

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Constitutive Modeling for Porous PLGA 85/15 Scaffold in Compression

Materials, Nondestructive Evaluation, and Pressure Vessels and Piping ◽

10.1115/imece2006-15240 ◽

2006 ◽

Author(s):

Linus Leung ◽

Josee Perron ◽

Hani E. Naguib

Keyword(s):

Constitutive Model ◽

Constitutive Modeling ◽

Saturation Pressure ◽

Mass Ratio ◽

Compressive Behavior ◽

Stress Strain ◽

Salt Leaching ◽

Strain Relationship ◽

Relationship Of ◽

Gas Foaming

Constitutive modeling of stress-strain relationship of open-celled PLGA 85/15 foams under compression was studied. A constitutive model for compressive behavior was directly derived from the morphology of a unit cubic cell. These constitutive equations describe the stress-strain relationship as a function of the foam's material properties and cell morphology, such as elastic modulus, yield stress, relative density, cell strut thickness, and cell size. To verify this model, uniaxial compression testing was performed on foam samples. Using the gas foaming/salt leaching method, the samples were prepared by using different foaming parameters such as salt/polymer mass ratio, saturation pressure, and saturation time. The comparisons of theoretical and experimental data demonstrate that the constitutive model using a cubic unit cell accurately describes the behavior of PLGA foams with low relative densities under compression.

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