Influence of the deformation heating on the flow behavior of 6063 alloy during compression at medium strain rates

AbstractThe flow behavior of 3104 aluminum alloy was investigated at temperatures ranging from 250°C to 500°C, and strain rates from 0.01 to 10 s−1 by isothermal compression tests. The true stress–strain curves were obtained from the measured load–stroke data and then modified by friction and temperature correction. The effects of temperature and strain rate on hot deformation behavior were represented by Zener–Hollomon parameter including Arrhenius term. Additionally, the influence of strain was incorporated considering the effect of strain on material constants. The derived constitution equation was applied to the finite element analysis of hot compression. The results show that the simulated force is consistent with the measured one. Consequently, the developed constitution equation is valid and feasible for numerical simulation in hot deformation process of 3104 alloy.

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Constitutive Modeling for Elevated Temperature Flow Behavior of ZHMn34-2-2-1 Manganese Brass

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.872.30 ◽

2017 ◽

Vol 872 ◽

pp. 30-37

Author(s):

Meng Han Wang ◽

Kang Wei ◽

Xiao Juan Li

Keyword(s):

Constitutive Model ◽

Strain Rate ◽

Flow Behavior ◽

Peak Stress ◽

Strain Rates ◽

Hollomon Parameter ◽

Prediction Ability ◽

Absolute Relative Error ◽

Deformation Behaviors ◽

State Stress

The hot compressive deformation behaviors of ZHMn34-2-2-1 manganese brass are investigated on Thermecmastor-Z thermal simulator over wide processing domain of temperatures (923K-1073K) and strain rates (0.01s-1-10s-1). The true stress-strain curves exhibit a single peak stress, after which the stress monotonously decreases until a steady state stress occurs, indicating a typical dynamic recrystallization. A revised constitutive model coupling flow stress with strain, strain rate and deformation temperature is established with the material constants expressed by polynomial fitting of strain. Moreover, better prediction ability of the constitutive model is achieved by implementation of a simple approach for modified the Zener-Hollomon parameter considering the compensation of strain rate and temperature increment. By comparing the predicted and experimented values, the correlation coefficient and mean absolute relative error are 0.997 and 2.363%, respectively. The quantitative statistical results indicate that the proposed constitutive model can precisely characterize the hot deformation behavior of ZHMn34-2-2-1 manganese brass.

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Rheo-Optics Studies in the Development of Hybrid Liquid Crystalline Based Mwir Polarizers

MRS Proceedings ◽

10.1557/proc-559-51 ◽

1999 ◽

Vol 559 ◽

Author(s):

P.T. Mather ◽

W. Barnes ◽

P.J. Hood ◽

T.J. Bunning

Keyword(s):

Liquid Crystalline ◽

Flow Behavior ◽

Optical Microscope ◽

Processing Technique ◽

Strain Rates ◽

Alignment Layer ◽

Small Pitch ◽

Wide Range ◽

Measured Polarization ◽

Free Films

ABSTRACTWe present here a rheo-optical study of the flow behavior of two cholesteric liquid crystals, one with a large pitch and one with a small pitch. The large pitch compound has been investigated as a possible fixed wavelength polarizer in the mid-wavelength infra-red region (3-5 micron). The investigation of these compounds is driven by their low melt viscosity and ability to vitrify order, and thus functionality, into films with a wide range of thickness. In our attempts to obtain consistent thin films with reproducible contrast ratios, we explored the defect textures of both compounds under a polarizing optical microscope. These materials were sheared at various strain rates and at various temperatures in an attempt to determine the best processing window for defect free films. The pitch lengths of the two materials investigated were 160 and 1330 nm. The flow behavior of the large pitch material resembles a pure nematic with defect refinement taking place under flow. The short pitch material exhibited the typical Grandjean oily streaks upon shearing followed by coarsening. Observations made during this rheological study were used to identify a processing technique for the large pitch materials. Upon application of a conventional buffed alignment layer, films with consistent quality were routinely made. The measured polarization contrast of >70:1 exceeds the values obtained from state-of-the art commercial polarizers in this wavelength regime.

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Effect of Deformation Heating on the Flow Behavior and Processing Maps of Al–Zn–Mg–Cu Alloy

MATERIALS TRANSACTIONS ◽

10.2320/matertrans.mt-m2020013 ◽

2020 ◽

Vol 61 (7) ◽

pp. 1414-1420

Author(s):

Qunying Yang ◽

Xiaoyong Liu ◽

Guodong Liu ◽

Guoqing Zhu

Keyword(s):

Flow Behavior ◽

Processing Maps ◽

Deformation Heating ◽

Cu Alloy

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Modeling of flow behavior for 7050-T7451 aluminum alloy considering microstructural evolution over a wide range of strain rates

Mechanics of Materials ◽

10.1016/j.mechmat.2016.01.006 ◽

2016 ◽

Vol 95 ◽

pp. 146-157 ◽

Cited By ~ 13

Author(s):

Guang Chen ◽

Chengzu Ren ◽

Zhihong Ke ◽

Jun Li ◽

Xinpeng Yang

Keyword(s):

Aluminum Alloy ◽

Microstructural Evolution ◽

Flow Behavior ◽

Strain Rates ◽

Wide Range

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Erebus Glacier Tongue, Mcmurdo Sound, Antarctica

Journal of Glaciology ◽

10.1017/s0022143000023340 ◽

1974 ◽

Vol 13 (67) ◽

pp. 27-35 ◽

Cited By ~ 39

Author(s):

G. Holdsworth

Keyword(s):

Shear Stress ◽

Strain Rate ◽

Shear Strain ◽

Longitudinal Strain ◽

Strain Rates ◽

Shear Strain Rate ◽

Mcmurdo Sound ◽

Glacier Tongue ◽

The Past ◽

Image Position

Examination of the past and present behaviour of the Erebus Glacier tongue over the last 60 years indicates that a major calving from the tongue appears to be imminent. Calculations of the regime of the tongue indicate that bottom melt rates may exceed 1 m a−1. By successive mapping of the ice tongue between the years 1947 and 1970, longitudinal strain-rates were determined using the change in distance between a set of 15 teeth, which are a prominent marginal feature of the tongue. Assuming a flow law for ice of the form where τ is the effective shear stress and is the effective shear strain-rate, values of the exponent n = 3 and B = 1 × 108 N m−2 are determined. These are in fair agreement with published values.

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A modified Arrhenius model for as-quenched Al-Mg-Si alloy considering the effect of cooling rate

Engineering Computations ◽

10.1108/ec-03-2020-0159 ◽

2020 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

Ruichao Guo ◽

Jianjun Wu ◽

Yinxiang Ren

Keyword(s):

Residual Stress ◽

Flow Stress ◽

Cooling Rate ◽

Flow Behavior ◽

Constitutive Behavior ◽

Strain Rates ◽

Arrhenius Model ◽

Content Type ◽

Stress Behavior ◽

Flow Stress Behavior

Purpose Accurate prediction of residual stress requires precise knowledge of the constitutive behavior of as-quenched material. This study aims to model the flow stress behavior for as-quenched Al-Mg-Si alloy. Design Methodology Approach In the present work, the flow behavior of as-quenched Al-Mg-Si alloy is studied by the hot compression tests at various temperatures (573–723 K), strain rates (0.1–1 s−1) and cooling rates (1–10 K/s). Flow stress behavior is then experimentally observed, and an Arrhenius model is used to predict the flow behavior. However, due to the fact that materials parameters and activation energy do not remain constant, the Arrhenius model has an unsatisfied prediction for the flow behavior. Considering the effects of temperatures, strain rates and cooling rates on constitutive behavior, a revised Arrhenius model is developed to describe the flow stress behavior. Findings The experimental results show that the flow stress increases by the increasing cooling rate, increasing strain state and decreasing temperature. In comparison to the experimental data, the revised Arrhenius model has an excellent prediction for as-quenched Al-Mg-Si alloy. Originality Value With the revised Arrhenius model, the flow behaviors at different quenching conditions can be obtained, which is an essential step to the residual stress prediction when the model is implemented in a finite element code, e.g. ABAQUS, in the future.

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A Comparative Study on Johnson Cook, Modified Zerilli–Armstrong, and Arrhenius-Type Constitutive Models to Predict Compression Flow Behavior of SnSbCu Alloy

Materials ◽

10.3390/ma12101726 ◽

2019 ◽

Vol 12 (10) ◽

pp. 1726 ◽

Cited By ~ 5

Author(s):

Tongyang Li ◽

Bin Zhao ◽

Xiqun Lu ◽

Hanzhang Xu ◽

Dequan Zou

Keyword(s):

Experimental Data ◽

Flow Behavior ◽

Constitutive Models ◽

Strain Range ◽

Type Model ◽

Strain Rates ◽

Compression Tests ◽

Predictive Values ◽

Specific Strain ◽

Optimum Model

The flow behavior of the SnSbCu alloy is studied experimentally by the compression tests in the range of the strain rates from 0.0001 to 0.1 s−1 and temperature from 293 to 413 K. Based on the experimental data, three constitutive models including the Johnson–Cook (J–C), modified Zerilli–Armstrong (Z–A), and Arrhenius-type (A-type) models are compared to find out an optimum model to describe the flow behavior of the SnSbCu alloy. The results show that the J–C model could predict the flow behavior of the SnSbCu alloy accurately only at some specific strain rates and temperature near the reference values. The modified Z–A and A-type constitutive models can give better fitting results than the J–C model. While, at high strains, the predictive values of the modified Z–A model have larger errors than those at low strains, which means this model has limitations at high strains. By comparison, the A-type model could predict the experimental results accurately at the whole strain range, which indicates that it is a more suitable choice to describe the flow behavior of the SnSbCu alloy in the focused range of strain rates and temperatures. The work is beneficial to solve the tribological problem of the bearing of the marine engine by integrating the accurate constitutive model into the corresponding numerical model.

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A Mathematical Description for the Stress-Strain Behavior of Annealed 2 1/4 Cr-1 Mo Steel

Journal of Pressure Vessel Technology ◽

10.1115/1.3454348 ◽

1976 ◽

Vol 98 (2) ◽

pp. 118-125 ◽

Cited By ~ 2

Author(s):

R. L. Klueh ◽

T. L. Hebble

Keyword(s):

Mathematical Description ◽

Flow Behavior ◽

True Strain ◽

Empirical Relationship ◽

Tensile Tests ◽

Strain Rates ◽

Strain Behavior ◽

Test Conditions ◽

Wide Range ◽

Strain Data

We have conducted a detailed series of tensile tests on one heat of annealed 2 1/4 Cr-1 Mo steel over the range 25 to 593°C (75 to 1100°F) and at nominal strain rates of 0.4, 0.04, 0.004, and 0.0004/min. To determine an empirical relationship to represent the flow behavior, we fitted the true-stress true-strain data from these tests to several proposed models. The models fit were those proposed by Hollomon, Ludwik, Ludwigson, and Voce. From a comparison of the standard error of estimate, the Voce equation was concluded to be the best mathematical description of the data under most test conditions and the best single representation over the wide range of test conditions.

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