Prediction of Flow Stress Behavior of 70Cr3Mo Back-Up Roll Steel Using Modified Zerilli-Armstrong Model

2014 ◽  
Vol 552 ◽  
pp. 247-250
Author(s):  
Fa Cai Ren ◽  
Jun Chen ◽  
Fei Chen
Keyword(s):  
Experimental Data ◽  
Flow Stress ◽  
Constitutive Model ◽  
Correlation Coefficient ◽  
Strain Rates ◽  
Compression Tests ◽  
Stress Strain ◽  
Roll Steel ◽  
Wide Range ◽  
Strain Data

The stress-strain data from hot compression tests over a wide range of temperatures (1173–1473 K at an interval of 100 K) and strain rates (0.01, 0.1, 1 and 10 s-1) were conducted using Gleeble-1500D thermo-mechanical simulator. A modified Zerilli-Armstrong constitutive model was developed using the experimental data of 70Cr3Mo back-up roll steel. The predictable efficiency of this model was evaluated by correlation coefficient and the value was 0.9902.

Stress-Strain Characteristics of Various Steels over a Wide Range of Strain-Rates and Temperatures

1973 ◽  
Vol 187 (1) ◽  
pp. 523-533 ◽  
Author(s):  
T. A. Dean ◽  
C. E. N. Sturgess
Keyword(s):  
High Speed ◽  
Strain Rates ◽  
Metal Working ◽  
Compression Tests ◽  
Stress Strain ◽  
Wide Range ◽  
Mechanical Press

Compression tests are described to determine the flow stresses of steel of specifications: En 1A, En 8, En 26, En 30B, En 58 and 6:5:2 and 18:4:1 high-speed steels, which are presented for use in the analysis of metal working operations. Testing temperatures of 600°C, 800°C, 1000°C and 1200°C were employed and using each of two high-speed hammers and a mechanical press, strain-rates ranging from approximately 12/s to 2500/s were obtained.

Modeling of Flow Stress for one New Kind of Metastable β Titanium Alloy at High Temperature

2011 ◽  
Vol 311-313 ◽  
pp. 716-721
Author(s):  
Zhe Jun Wang ◽  
Hong Fu Qiang ◽  
Xue Ren Wang
Keyword(s):  
Titanium Alloy ◽  
High Temperature ◽  
Flow Stress ◽  
Constitutive Model ◽  
Flow Behavior ◽  
Accurate Estimate ◽  
Compression Tests ◽  
Stress Strain ◽  
Nonlinear Constitutive Equation ◽  
Peak Value

Based on the characteristics of the flow stress curves for one new kind of metastable Ti2448 titanium alloy from isothermal hot compression tests, the constitutive model was developed to describe the relation between flow stress and strain, strain rate, deformation temperature completely. During this process, the flow behavior of alloy at high temperature undergo flow softening caused by dynamic recovery (DRV) was modeled by the adopted hyperbolic sine function based on the unified viscoplasticity theory, the further drop in flow stress after the peak value in stress-strain curves was assumed to be caused by temperature rise and the constitutive model was modified accordingly. Additionally, the material constants were determined by optimization strategies, which is a new method to solve the nonlinear constitutive equation. The stress-strain curves predicted by the developed constitutive model well agree with experimental results, which confirms that the developed constitutive model gives an accurate estimate of the flow stress of Ti2448 titanium alloy and can provide an effect method to model the flow behavior of metastable titanium alloy at high temperature.

Nonlinear Viscoelastic Response of Amorphous Elastomers to Constant Strain Rates

1963 ◽  
Vol 36 (3) ◽  
pp. 682-696 ◽  
Author(s):  
Thor L. Smith
Keyword(s):  
Strain Rate ◽  
Constant Strain Rate ◽  
Relaxation Modulus ◽  
Nonlinear Effects ◽  
Published Data ◽  
Strain Rates ◽  
Stress Strain ◽  
Linear Viscoelastic Material ◽  
Wide Range ◽  
Strain Data

Abstract Tensile stress-strain curves determined at constant strain rates are nonlinear because relaxation of stress generally occurs during a test and also because of inherent nonlinear effects. To develop a method for determining the conditions under which time and nonlinear effects are separable, consideration was first given to a linear viscoelastic material. It was shown that stress-strain curves determined at different strain rates superpose to yield a single curve on a plot of log σ(ε, t)/ε vs. log t, where σ(ε, t) is the stress, a function of the strain ε and the time t; by definition t equals ε/ε where ε is the strain rate. The quantity σ(ε, t)/ε was called the constant-strain rate modulus F(t) which is related exactly to the stress-relaxation modulus E(t) by the equation E(t)=F(t)(1+m) where m=d log F(t)/d log t. For amorphous elastomers tested in tensions over a wide range of strain, it was proposed that stress-strain curves determined at constant strain rates can be represented by F(t)=g(ε)σ(ε,t)/ε where g(ε) is a function only of strain and approaches unity as the strain goes to zero. To test this equation, an analysis was made of stress-strain curves of an SBR gum vulcanizate measured to rupture at numerous strain rates at 10 temperatures between −42.8 and 93.3° C. From − 34.4 to 93.3° C, g (ε) was found to be independent of both time and temperature, but at −42.8° C for strains greater than about unity, g(ε) was found to be different. The functional form of g(ε) was compared with that predicted by three different analytical expressions for representing stress-strain data. To show further the advantages of F(t) for representing stress-strain data determined at different strain rates and temperatures, previously published data on the NBS polyisobutylene were presented on a plot of log F(t)298/T vs. log t/aT. From the composite curve, E(t) was calculated and found to be in close agreement with published data.

scholarly journals A Modified Constitutive Model for the Description of the Flow Behavior of the Ti-10V-2Fe-3Al Alloy during Hot Plastic Deformation

Metals ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 844 ◽  
Author(s):  
Wang ◽  
Shen ◽  
Zhang ◽  
Ning
Keyword(s):  
Flow Stress ◽  
Constitutive Model ◽  
Strain Rate ◽  
Elevated Temperatures ◽  
Flow Behavior ◽  
Strain Rates ◽  
Compression Tests ◽  
Flow Curves ◽  
Deformation Parameters ◽  
Predicted Values

The hot deformation behavior of the aerospace Ti-10-2-3 alloy was investigated by isothermal compression tests at temperatures of 740 to 820 °C and strain rates of 0.0005 to 10 s−1. The results show that the studied alloy is extremely sensitive to deformation parameters, like the temperature and strain rate. The temperature mainly affects the magnitude of flow stress at larger strains, while the strain rate not only affects the value of flow stress but also the shape of the flow curves. At low strain rates, the flow stress increases with strain, followed by a broad peak and then remains almost constant. At high strain rates, the flow curves exhibit a hardening to a sharp peak at small strains, followed by a rapid dropping to a plateau caused by dynamic softening. In order to describe such flow behavior, a constitutive model considering the effect of deformation parameters was developed as an extension of an existing constitutive model. The modified constitutive model (MC) was obtained based on the original constitutive model (OC) by introducing a new parameter to compensate for the error between the experimental data and predicted values. Compared to the original model, the developed model provides a better description of the flow behavior of Ti-10-2-3 alloy at elevated temperatures over the specified deformation domain.

scholarly journals Microstructure Evaluation and Constitutive Modeling of AISI-1045 Steel for Flow Stress Prediction under Hot Working Conditions

Symmetry ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 782
Author(s):  
Mohanraj Murugesan ◽  
Muhammad Sajjad ◽  
Dong Won Jung
Keyword(s):  
Flow Stress ◽  
Constitutive Equation ◽  
Constitutive Model ◽  
Stress Strain ◽  
Strain Data ◽  
Aisi 1045 Steel ◽  
Aisi 1045 ◽  
Stress Prediction ◽  
1045 Steel ◽  
Actual Test

In the field of engineering, automobile and aerospace components are manufactured based on the desired applications from the metal forming process. For producing better quality of both symmetry and asymmetry mechanical parts, understanding the material deformation and analytical representation of the material ductility behavior for the working material is necessary as the forming procedures carried out mostly in the warm processing conditions. In this work, the hot tensile test flow stress-strain data were utilized to construct the constitutive equation for describing AISI-1045 steel material hot deformation behavior, and the test conditions, such as deformation temperatures and strain rates were 750–950 ° C and 0.05–1.0 s − 1 , respectively. The surface morphology and elemental identification analysis were performed using the field emission scanning electron microscopy (FESEM) coupled with the energy-dispersive X-ray spectroscopy (EDS) mapping setup. In this work, the Arrhenius-type constitutive equation, including the strain compensation, was used to formulate the flow stress prediction model for capturing the material behavior. Besides, the Zener-Hollomon parameter was altered, employing incorporating the effect of strain rate and strain on the flow stress. The empirical model approach was employed to estimate the material model constants from the constitutive equation using the actual test measurements. The population metrics such as coefficient of determination ( R 2 ), sample standard deviation of the error (SSD), standard error of the regression (SER), coefficient of residual variation (CRV), and average absolute relative error (AARE) was employed to confirm the predictability of the proposed models. The computed results are discussed in detail, using numerical and graphical verification’s. From the graphical comparison, the flow stress-strain data achieved from the proposed constitutive model are in good agreement with the actual test measurements. The constitutive model prediction accuracy is found to be improved, like the prediction error range from 3.678% to 2.984%. This evidence proves to be feasible as the newly developed model displayed a significant improvement against the experimental observations.

scholarly journals Hot Deformation Behavior and Processing Map of GH901 Superalloy

Metals ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1808
Author(s):  
Rui Ma ◽  
Lulu Li ◽  
Ruixue Zhai ◽  
Xiangnan Meng ◽  
Jun Zhao
Keyword(s):  
Flow Stress ◽  
Constitutive Model ◽  
Thermal Processing ◽  
Processing Map ◽  
Simulation Software ◽  
Strain Rates ◽  
Compression Tests ◽  
Isothermal Forging ◽  
Forging Process ◽  
Element Simulation

During the forging process GH901 superalloys easily produce cracks and defects, such as coarse crystals in tissues, which affect the performance of the alloy. Using GH901 nickel-based alloy, high-temperature compression tests at deformation temperatures of 990, 1040, 1090 and 1140 °C were carried out in a Thermecmastor-Z thermal simulator, with strain rates 0.001, 0.01, 0.1 and 1 s−1. Next, the isothermal forging process of a GH901 disc was simulated using DEFORM finite element simulation software. The results showed that with the increase in deformation temperatures and the decrease in strain rates, the flow stress clearly decreased. The flow stress constitutive model of GH901 superalloy under ε0.3 and the flow stress constitutive model for strain compensation were obtained. The processing map was built, and a reasonable range of thermal processing was obtained. Meanwhile, the isothermal forging simulation verified the reliability of the thermal processing range of the alloy.

Stress-Strain Characteristics of Various Steels over a Wide Range of Strain-Rates and Temperatures

1973 ◽  
Vol 187 (1) ◽  
pp. 523-533 ◽  
Author(s):  
T. A. Dean ◽  
C. E. N. Sturgess
Keyword(s):  
High Speed ◽  
Strain Rates ◽  
Metal Working ◽  
Compression Tests ◽  
Stress Strain ◽  
Wide Range ◽  
Mechanical Press

Compression tests are described to determine the flow stresses of steel of specifications: En 1A, En 8, En 26, En 30B, En 58 and 6:5:2 and 18:4:1 high-speed steels, which are presented for use in the analysis of metal working operations. Testing temperatures of 600°C, 800°C, 1000°C and 1200°C were employed and using each of two high-speed hammers and a mechanical press, strain-rates ranging from approximately 12/s to 2500/s were obtained.

A Nonlinear Visco-Hyper Elastic Constitutive Model for Modeling Behavior of Polyurea at Large Deformations

2019 ◽  
Author(s):  
Shank S. Kulkarni ◽  
Alireza Tabarraei
Keyword(s):  
Experimental Data ◽  
Constitutive Model ◽  
Viscoelastic Model ◽  
Viscoelastic Behavior ◽  
Strain Rates ◽  
Strain Behavior ◽  
Strain And Strain Rate ◽  
Proposed Model ◽  
Wide Range ◽  
Hyper Elastic

Abstract The fantastic properties of polyurea such as flexibility, durability, and chemical resistance have brought it a wide range of application in various industries. Effective prediction of the response of polyurea under different loading and environmental conditions necessitates the development of an accurate constitutive model. Similar to most polymers, the behavior of polyurea depends on both the strain and strain rate. Therefore, the constitutive model should be able to capture both these effects on the response of polyurea. To achieve this objective, in this paper, a nonlinear visco-hyper elastic constitutive model is developed by the superposition of a hyperelastic and a viscoelastic model. The proposed constitutive model can capture the behavior of polyurea under compressive as well as tensile loading conditions at various strain rates. Four parameter Ogden model is used to model the hyperelastic behavior of polyurea. The viscoelastic behavior is modeled using a three-parameter standard linear solid (SLS) model. The material parameters of the model are found by curve fitting of the proposed model to the experimental data. Comparison of the proposed model and the experimental data shows that the proposed model can closely reproduce the stress-strain behavior of polyurea under a wide range of strain rates (−6500 to 294 /s).

The Constitutive Model for High Temperature Flow Behavior of SiC/6168Al Composite

2015 ◽  
Vol 1089 ◽  
pp. 37-41
Author(s):  
Jiang Wang ◽  
Sheng Li Guo ◽  
Sheng Pu Liu ◽  
Cheng Liu ◽  
Qi Fei Zheng
Keyword(s):  
Constitutive Model ◽  
Hot Deformation ◽  
Flow Behavior ◽  
Type Equation ◽  
Strain Rate Range ◽  
Compression Tests ◽  
Stress Strain ◽  
Hollomon Parameter ◽  
Proposed Model ◽  
Relationship Of

The hot deformation behavior of SiC/6168Al composite was studied by means of hot compression tests in the temperature range of 300-450 °C and strain rate range of 0.01-10 s-1. The constitutive model was developed to predict the stress-strain curves of this composite during hot deformation. This model was established by considering the effect of the strain on material constants calculated by using the Zenter-Hollomon parameter in the hyperbolic Arrhenius-type equation. It was found that the relationship of n, α, Q, lnA and ε could be expressed by a five-order polynomial. The stress-strain curves obtained by this model showed a good agreement with experimental results. The proposed model can accurately describe the hot flow behavior of SiC/6168Al composite, and can be used to numerically analyze the hot forming processes.

Constitutive Modeling for Flow Stress Behavior of Nimonic 80A Superalloy During Hot Deformation Process

2016 ◽  
Vol 35 (3) ◽  
pp. 327-336 ◽  
Author(s):  
Sendong Gu ◽  
Liwen Zhang ◽  
Chi Zhang ◽  
Wenfei Shen
Keyword(s):  
Flow Stress ◽  
Constitutive Model ◽  
Hot Deformation ◽  
Critical Strain ◽  
Volume Fraction ◽  
Constitutive Models ◽  
Avrami Equation ◽  
Peak Strain ◽  
Compression Tests ◽  
Nimonic 80A

AbstractThe hot deformation characteristics of nickel-based alloy Nimonic 80A were investigated by isothermal compression tests conducted in the temperature range of 1,000–1,200°C and the strain rate range of 0.01—5 s–1on a Gleeble-1500 thermomechanical simulator. In order to establish the constitutive models for dynamic recrystallization (DRX) behavior and flow stress of Nimonic 80A, the material constantsα,nand DRX activation energyQin the constitutive models were calculated by the regression analysis of the experimental data. The dependences of initial stress, saturation stress, steady-state stress, dynamic recovery (DRV) parameter, peak strain, critical strain and DRX grain size on deformation parameters were obtained. Then, the Avrami equation including the critical strain for DRX and the peak strain as a function of strain was established to describe the DRX volume fraction. Finally, the constitutive model for flow stress of Nimonic 80A was developed in DRV region and DRX region, respectively. The flow stress values predicted by the constitutive model are in good agreement with the experimental ones, which indicates that the constitutive model can give an accurate estimate for the flow stress of Nimonic 80A under the deformation conditions.

Sign in / Sign up

Export Citation Format

Share Document