Evaluating the flow stress of electrical steel under cold rolling in terms of the strain-rate hardening effect

Some results of an experimental study on high strain rate deformation of TC21 alloy are discussed in this paper. Cylindrical specimens of the TC21 alloys both in binary morphology and solution and aging morphology were subjected to high strain rate deformation by direct impact using a Split Hopkinson Pressure Bar. The deformation process is dominated by both thermal softening effect and strain hardening effect under high strain rate loading. Thus the flow stress doesn’t increase with strain rate at the strain hardening stage, while the increase is obvious under qusi-static compression. Under high strain rate, the dynamic flow stress is higher than that under quasi-static and dynamic flow stress increase with the increase of the strain rate, which indicates the strain rate hardening effect is great in TC21 alloy. The microstructure affects the dynamic mechanical properties of TC21 titanium alloy obviously. Under high strain rate, the solution and aging morphology has higher dynamic flow stress while the binary morphology has better plasticity and less prone to be instability under high strain rate condition. Shear bands were found both in the solution and aging morphology and the binary morphology.

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Sensitivity Analysis of the Material Flow Stress in Machining

Manufacturing ◽

10.1115/imece2003-41655 ◽

2003 ◽

Cited By ~ 4

Author(s):

Ning Fang

Keyword(s):

Sensitivity Analysis ◽

Flow Stress ◽

Aluminum Alloys ◽

Strain Rate ◽

Strain Hardening ◽

Material Flow ◽

Chemical Compositions ◽

Wide Range ◽

Strain Rate Hardening ◽

Factor Governing

Among the effects of strain hardening, strain-rate hardening, and temperature softening, it has long been argued about which effect is predominant in governing the material flow stress in machining. This paper compares four material constitutive models commonly employed, including Johnson-Cook’s model, Oxley’s model, Zerilli-Armstrong’s model, and Maekawa et al.’s model. A new quantitative sensitivity analysis of the material flow stress is performed based on Johnson-Cook’s model covering a wide range of engineering materials, including plain carbon steels with different carbon contents, alloyed steels, aluminum alloys with different chemical compositions and heat treatment conditions, copper and copper alloys, iron, nickel, tungsten alloys, etc. It is demonstrated that the first predominant factor governing the material flow stress is either strain hardening or thermal softening, depending on the specific work material employed and the varying range of temperatures. Strain-rate hardening is the least important factor governing the material flow stress, especially when machining aluminum alloys.

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Mechanical Behavior and Constitutive Equation of Concrete under High-Temperature Dynamical Conditions

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.228-229.303 ◽

2011 ◽

Vol 228-229 ◽

pp. 303-308

Author(s):

Bin Jia ◽

Zheng Liang Li ◽

Jun Lin Tao ◽

Chun Tao Zhang

Keyword(s):

High Temperature ◽

Constitutive Equation ◽

Strain Rate ◽

Mechanical Behavior ◽

Test Data ◽

Dynamical Behavior ◽

Hardening Effect ◽

Failure Evolution ◽

Different Temperatures ◽

Strain Rate Hardening

SPHB tests of concrete under different temperatures and various loading conditions are completed, and high-temperature dynamical behavior of concrete is obtained. Dynamical mechanical behavior of concrete with high temperature is affected by not only the strain rate effect, but also the high temperature weakening effect, and the strain rate hardening effect is coupled with high temperature weakening effect, but the latter has greater influence. Concrete failure evolution is described on basis of the damage factor, the intercoupling strain rate hardening effect and temperature weakening effect are simply set as mutually independent factors, each parameter is respectively fitted with test data, finally, concrete constitutive equation under high-temperature dynamical conditions is established, and comparative analysis with test data are conducted, indicating good coincidence with test results.

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Analytical modelling of edge chipping in scratch of soda-lime glass considering strain-rate hardening effect

Ceramics International ◽

10.1016/j.ceramint.2021.06.069 ◽

2021 ◽

Author(s):

Haoyu Shi ◽

Gongyu Liu ◽

Guilin Yang ◽

Qingzhen Bi ◽

Yongjie Zhao ◽

...

Keyword(s):

Strain Rate ◽

Soda Lime ◽

Analytical Modelling ◽

Soda Lime Glass ◽

Edge Chipping ◽

Hardening Effect ◽

Strain Rate Hardening

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High Temperature High Strain-Rate Tensile and Compressive Deformation Behaviors of Cu-Zn-Sn-Al Alloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.817.55 ◽

2015 ◽

Vol 817 ◽

pp. 55-62

Author(s):

Qiang Song Wang ◽

Dong Mei Liu ◽

Guo Liang Xie ◽

Wei Bin Xie ◽

Yang Li ◽

...

Keyword(s):

High Temperature ◽

High Strain Rate ◽

Strain Rate ◽

High Strain ◽

Al Alloy ◽

Softening Effect ◽

Α Phase ◽

Hardening Effect ◽

Deformation Behaviors ◽

Strain Rate Hardening

The present work gives a systematic study on the high temperature and high strain-rate deformation behaviors of a two-phase α/β Cu-Zn-Sn-Al alloy, by combining the split Hopkinson bar experiments and microstructural investigations. The results show that under high strain-rate, both the dislocation slip and deformation twins within the α phase contribute to the plastic strengthening of Cu-Zn-An-Al alloy, resulting in the strain-rate-hardening effect. As the deformation temperature increases, the shapes of the stress-strain curves are mainly influenced by the temperature-softening effect and the dynamic recrystallization of the α phase. Finally, material constants regarding the strain-rate-hardening and temperature-softening effects are determined, based on the Johnson-Cook constitutive model. The results show that compared with other metallic materials, the present Cu-Zn-Sn-Al alloy has a relatively stronger strain-rate-hardening effect and weaker temperature-softening effect.

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Plastic Constitutive Model and Analysis of Flow Stress of 40Cr Quenched and Tempered Steel

ISRN Mechanical Engineering ◽

10.1155/2013/490750 ◽

2013 ◽

Vol 2013 ◽

pp. 1-6

Author(s):

Wang Xiao-qiang ◽

Zhu Wen-juan ◽

Cui Feng-kui ◽

Li Yu-xi

Keyword(s):

Flow Stress ◽

Numerical Analysis ◽

Constitutive Model ◽

Cold Rolling ◽

Strain Rate ◽

Temperature Sensitivity ◽

Solution Process ◽

Strain Rates ◽

Material Parameters ◽

Quenched And Tempered Steel

To solve the problem of the accuracy of the numerical simulations of cold rolling, the thermomechanical responses of 40Cr under uniaxial compression loading are presented. The strain rates include quasistatic (0.004 s−1) at temperature of 293 K and dynamic loading regime (632 s−1~5160 s−1) at temperature regime (293 K~673 K). Significant strain rate and temperature sensitivity are measured. Based on these observations, the Johnson-Cook phenomenological constitutive model is proposed to predict the mechanical behavior of the 40Cr over wide ranges of strain rate and temperature. The solution process of the equation parameters is given. Correlations with this Johnson-Cook model are shown very close to the observed responses. Important material parameters are provided to the application of numerical analysis in project.

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A New Quantitative Sensitivity Analysis of the Flow Stress of 18 Engineering Materials in Machining

Journal of Engineering Materials and Technology ◽

10.1115/1.1857935 ◽

2005 ◽

Vol 127 (2) ◽

pp. 192-196 ◽

Cited By ~ 35

Author(s):

N. Fang

Keyword(s):

Sensitivity Analysis ◽

Flow Stress ◽

Strain Rate ◽

Strain Hardening ◽

Material Flow ◽

Predominant Factor ◽

Strain Rate Hardening ◽

Engineering Materials ◽

Specific Material ◽

Factor Governing

It has long been argued about which effect, among the effects of strain hardening, strain-rate hardening, and temperature softening, is predominant in governing the material flow stress in machining. This paper presents a new quantitative sensitivity analysis of the flow stress of 18 engineering materials based on the well-known Johnson-Cook model. It is demonstrated that the first predominant factor governing the material flow stress is either strain hardening or thermal softening, depending on the specific material employed and the varying range of temperatures. Strain-rate hardening is the least important factor governing the material flow stress, especially when machining aluminum alloys.

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Dynamic finite element simulation of wheel–rail contact response for the straight track case

Advances in Structural Engineering ◽

10.1177/1369433220971733 ◽

2020 ◽

pp. 136943322097173

Author(s):

Xiongfei Zhou ◽

Lin Jing ◽

Xiaoqi Ma

Keyword(s):

Finite Element ◽

Strain Rate ◽

Strain Rate Effect ◽

Rate Effect ◽

Rolling Contact ◽

Inertia Effect ◽

Hardening Effect ◽

Train Speed ◽

Strain Rate Hardening ◽

Contact Response

The dynamic effects, mainly including the inertia effect and strain-rate effect, on the dynamic wheel–rail contact behavior become more and more serious as the train speed increases. The inertia effect can be automatically taken into account in explicit finite element analysis codes, while the strain-rate effect needs to be considered via inputting the related material parameters. In the present paper, the influence of strain rate on the dynamic wheel–rail contact response for the straight track case was explored, based on a 3D wheel–rail rolling contact finite element model, via LS-DYNA/explicit algorithm. Effects of the axle load and train speed on typical dynamic wheel–rail responses were discussed, and the results indicate that the coupled train speed with strain rate has a non-negligible influence on dynamic contact responses. The strain rate hardening effect increases the maximum contact pressure and stress, and inhibits the plastic deformation of the wheel–rail system. A rate-sensitive factor (RSF) was then introduced to describe the strain rate hardening effect, confirming that the rail is more sensitive to strain rate compared to the wheel. Finally, an error analysis of the wheel–rail Hertz contact theory was conducted, which further verify the differences between elastic and elastic-plastic contact solutions.

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High-Strain-Rate Response of a Specially-Made Copper Sample

Materials Science Forum ◽

10.4028/www.scientific.net/msf.817.35 ◽

2015 ◽

Vol 817 ◽

pp. 35-41

Author(s):

Dong Mei Liu ◽

Qiang Song Wang ◽

Guo Liang Xie ◽

Wei Bin Xie ◽

Yang Li ◽

...

Keyword(s):

High Strain Rate ◽

Strain Rate ◽

High Temperatures ◽

High Strain ◽

Copper Sample ◽

Dislocation Slip ◽

Softening Effect ◽

Hardening Effect ◽

Dynamic Recrystallization Behavior ◽

Strain Rate Hardening

In the present study, a systematic study on both the high strain-rate tensile and compressive deformation behaviors of a specially-made copper sample have been carried out at different high temperatures, by using the split Hopkinson bar experiments. The Johnson-Cook constitutive model was used to model the high strain-rate responses of the specimen at high temperatures. The results showed that compared with other metallic materials, the specially-made copper sample had a relatively stronger strain-rate-hardening effect and weaker temperature-softening effect. Evolution of the microstructure suggests that under high strain-rate, both the dislocation slip and deformation twins contribute to the plastic strengthening of the copper specimen, resulting in the strain-rate-hardening effect. And the dynamic recrystallization behavior plays an important role during the high strain-rate deformation process at the high temperatures.

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Viscoplastic flow of functional cellular materials with use of peridynamics

Meccanica ◽

10.1007/s11012-021-01383-7 ◽

2021 ◽

Author(s):

Eligiusz Postek ◽

Zdzisław Nowak ◽

Ryszard B. Pęcherski

Keyword(s):

Strain Rate ◽

Copper Sample ◽

Metallic Foam ◽

Viscoplastic Flow ◽

Hardening Effect ◽

Load Carrying ◽

Open Cell Foam ◽

Taylor Impact ◽

The Subject ◽

Strain Rate Hardening

AbstractThe subject of the study is the deformation of the oxygen-free high conductivity copper. The copper sample is given in the form of a foam. The sample undergoes an impact into an elastic wall. The strain rate hardening effect is investigated. The numerical model of the open-cell foam skeleton is prepared in the framework of the peridynamics method. The dynamic process of compression with different impact velocities is simulated. It has been found that the strain rate hardening effect is essential for the load-carrying capacity of the material under study. Taylor impact test of solid cylinder analysis precedes the analysis of the metallic foam.

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