Hot Deformation Behavior and Constitutive Modeling of Alloy 800H Considering Effectsof Strain

AbstractHigh-temperature single-pass compression experiments were conducted on alloy 800H using a Gleeble 3500 thermal-mechanical simulation testing machine, and hot deformation behaviors at temperatures of 1,000–1,150 °C and strain rates of 0.01–1 s–1 were investigated. The results revealed that dynamic recrystallization (DRX) behavior occurred more easily under deformation conditions with relatively low strain rates and high deformation temperatures. By taking the influence of strain on the hot deformation behavior into consideration, a strain-dependent hyperbolic sine constitutive model was constructed. Based on this revised constitutive model, flow stress during deformation was predicted. The linear relation between the predicted value and the experimental result was as high as 0.99648, and the absolute average relative error was 2.019 %. Thus, it was demonstrated that the strain-dependent analysis provided a constitutive model that was able to precisely predict flow stress under experimental conditions.

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On the Capability of Logarithmic-Power Model for Prediction of Hot Deformation Behavior of Alloy 800H at High Strain Rates

High Temperature Materials and Processes ◽

10.1515/htmp-2018-0022 ◽

2019 ◽

Vol 38 (2019) ◽

pp. 84-91 ◽

Cited By ~ 2

Author(s):

E. Shafiei ◽

A. Soltani Tehrani

Keyword(s):

Flow Stress ◽

Constitutive Equation ◽

Hot Deformation ◽

Deformation Behavior ◽

High Strain ◽

Power Model ◽

Strain Rates ◽

Hot Deformation Behavior ◽

High Strain Rates ◽

Alloy 800H

AbstractIn this study, the logarithmic-power model has been used to predict hot deformation behavior of alloy 800H at high temperatures. This is for the first time that the logarithmic-power model is examined to model the flow stress curves with negligible flow softening at high strain rates. To this end, flow stress curves of alloy 800H obtained at deformation temperatures from 850°C to 1050°C and at strain rates of 5 and 10 S−1 were employed. The Johnson–Cook model and Shafiei constitutive equation were also used to prove the accuracy of the logarithmic-power model in prediction of flow stress curves of alloy 800H. Evaluation of mean error of flow stress at different deformation conditions showed that the logarithmic-power model can give a more precise estimation of flow stress curves than Johnson–Cook model. Furthermore, it was found out that the accuracy of the Logarithmic-power model and Shafiei constitutive equation was roughly the same in terms of maximum errors obtained in prediction of flow stress curves. Accordingly, it can be concluded that the logarithmic-power model can be employed as a comprehensive model for a wide range of deformation conditions.

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Hot Deformation Behavior of a New Al–Mn–Sc Alloy

Materials ◽

10.3390/ma13010022 ◽

2019 ◽

Vol 13 (1) ◽

pp. 22

Author(s):

Weiqi Kang ◽

Yi Yang ◽

Sheng Cao ◽

Lei Li ◽

Shewei Xin ◽

...

Keyword(s):

Flow Stress ◽

Hot Deformation ◽

Deformation Behavior ◽

Material Model ◽

Strain Rates ◽

Hot Workability ◽

Hot Deformation Behavior ◽

Hollomon Parameter ◽

Dynamic Material Model ◽

Optimal Processing

The hot deformation behavior of a new Al–Mn–Sc alloy was investigated by hot compression conducted at temperatures from 330 to 490 °C and strain rates from 0.01 to 10 s−1. The hot deformation behavior and microstructure of the alloy were significantly affected by the deformation temperatures and strain rates. The peak flow stress decreased with increasing deformation temperatures and decreasing strain rates. According to the hot deformation behavior, the constitutive equation was established to describe the steady flow stress, and a hot processing map at 0.4 strain was obtained based on the dynamic material model and the Prasad instability standard, which can be used to evaluate the hot workability of the alloy. The developed hot processing diagram showed that the instability was more likely to occur in the higher Zener–Hollomon parameter region, and the optimal processing range was determined as 420–475 °C and 0.01–0.022 s−1, in which a stable flow and a higher power dissipation were achieved.

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Hot deformation behavior of TC18 titanium alloy

Thermal Science ◽

10.2298/tsci1305523j ◽

2013 ◽

Vol 17 (5) ◽

pp. 1523-1528

Author(s):

Bao-Hua Jia ◽

Wei-Dong Song ◽

Hui-Ping Tang ◽

Jian-Guo Ning

Keyword(s):

Titanium Alloy ◽

Flow Stress ◽

Strain Rate ◽

Hot Deformation ◽

Deformation Behavior ◽

True Strain ◽

Testing Machine ◽

Constitutive Relationship ◽

Compression Tests ◽

Hot Deformation Behavior

Isothermal compression tests of TC18 titanium alloy at the deformation temperatures ranging from 25?C to 800?C and strain rate ranging from 10-4 to 10-2 s-1 were conducted by using a WDW-300 electronic universal testing machine. The hot deformation behavior of TC18 was characterized based on an analysis of the true stress-true strain curves of TC18 titanium alloy. The curves show that the flow stress increases with increasing the strain rate and decreases with increasing the temperature, and the strain rate play an important role in the flow stress when increasing the temperatures. By taking the effect of strain into account, an improved constitutive relationship was proposed based on the Arrhenius equation. By comparison with the experimental results, the model prediction agreed well with the experimental data, which demonstrated the established constitutive relationship was reliable and can be used to predict the hot deformation behavior of TC18 titanium alloy.

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Modeling the Hot Deformation Behavior of 1565ch Aluminum Alloy

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.684.35 ◽

2016 ◽

Vol 684 ◽

pp. 35-41 ◽

Cited By ~ 3

Author(s):

S.V. Rushchits ◽

E.V. Aryshensky ◽

S.M. Sosedkov ◽

A.M. Akhmed'yanov

Keyword(s):

Aluminum Alloy ◽

Flow Stress ◽

Strain Rate ◽

Hot Deformation ◽

Deformation Behavior ◽

Static Recrystallization ◽

Strain Rates ◽

Strain Resistance ◽

Hot Deformation Behavior ◽

Zirconium Addition

The deformation behavior of 1565ch alloy under the plane-strain conditions in the temperature range of 350–490 оС and strain rates range of 0,1–10 s-1 is studied. The expression for steady flow stress as the functions of temperature of deformation and strain rate is obtained. It is established that 1565ch alloy with zirconium addition shows higher strain resistance and less tendency to dynamic and static recrystallization than AMg6.

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Hot Deformation Behavior of As-Cast Mg-9Gd-2.5Y-Nd-0.5Zr Mg Alloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.788.45 ◽

2014 ◽

Vol 788 ◽

pp. 45-51

Author(s):

Yong Biao Yang ◽

Zhi Min Zhang ◽

Feng Li Ren ◽

Qiang Wang

Keyword(s):

Flow Stress ◽

Magnesium Alloy ◽

Hot Deformation ◽

Deformation Behavior ◽

Dynamic Recovery ◽

Strain Rates ◽

Hot Deformation Behavior ◽

Hollomon Parameter ◽

Temperature Range ◽

Parameter Function

The elevated temperature flow stress behavior of Mg-9Gd-2.5Y-1Nd-0.5Zr magnesium alloy was carried out by Gleeble-1500 thermal mechanical simulator in the temperature range of 460-520°C and in strain rates of 0.0005~1s-1 at a strain of 0.6. The optical microscopy was used for microstructure characterization. The results showed that the flow stress increases with increasing strain rates and decreasing temperature. All the deformed magnesium alloy specimens show a dynamic recovery characters in the temperature range from 460~500°C, and show dynamic recrystallization characters at 520°C. The flow stress of this alloy can be represented by Zener-Hollomon parameter function, and values of related parameters A, α and n, are 2.24×1013s-1、0.027MPa-1 and 2.93, respectively. Its activation energy for hot deformation Q is 212.6kJ/mol.

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Hot Deformation Behavior and Constitutive Equation of Mg-4Al-3Ca -1.5Zn-1Nd-0.2Mn Magnesium Alloy As-Extruded

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.900.588 ◽

2014 ◽

Vol 900 ◽

pp. 588-591

Author(s):

Gang Chen ◽

Wei Chen ◽

Guo Wei Zhang ◽

Jing Zhai ◽

Li Ma ◽

...

Keyword(s):

Activation Energy ◽

Flow Stress ◽

Magnesium Alloy ◽

Constitutive Equation ◽

Constitutive Equations ◽

Hot Deformation ◽

Deformation Behavior ◽

Strain Rates ◽

Compression Tests ◽

Hot Deformation Behavior

The deformation behavior and constitutive equation of Mg-4Al-3Ca-1.5Zn-1Nd-0.2Mn alloy were investigated using hot compression tests at the temperatures range of 200, 250, 300, and 350°C with the constant strain rates of 0.001, 0.01, 0.1 And1 s-1. The influence of strain was also incorporated in the constitutive equation by considering the effects of strain on material constants which are consist of A, α, β, n and activation energy Q. The predicted flow stress curves using the proposed constitutive equations well agree with the experimental results of the flow stress for experimental Alloy.

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The Hot Deformation Behavior and Hot Processing Map of CL60 Rail Wheel Steel

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.602-604.2006 ◽

2012 ◽

Vol 602-604 ◽

pp. 2006-2010

Author(s):

Fei Zhao ◽

Yan Yan ◽

Yong Hai Ren

Keyword(s):

Flow Stress ◽

Strain Rate ◽

Hot Deformation ◽

Deformation Behavior ◽

Wheel Steel ◽

Strain Rates ◽

Peak Strain ◽

Processing Maps ◽

Hot Deformation Behavior ◽

Experimental Conditions

The hot deformation behavior of CL60 rail wheel steel has been studied by employing both processing maps and microstructural observations. Tests are performed at temperatures of 800—1100°C and strain rates of 0.1s-1—5s-1 and the flow stress data obtained from the tests are used to develop processing maps. The microstructural evolution of deformed samples is also examined on the basis of optical microscopic observations. The result indicates that under experimental conditions this alloy shows dynamic recrystallization(RDX) characteristics during hot compression deformation. Both deformation temperatures and strain rates have obvious influence on flow stress and its corresponding peak strain, which increase gradually with decreasing temperature and increasing strain rate. RDX occurred at higher temperature and lower strain rate.

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Study on hot deformation behavior of homogenized Mg-8.5Gd-4.5Y-0.8Zn-0.4Zr alloy using a combination of strain-compensated Arrhenius constitutive model and finite element simulation method

Journal of Magnesium and Alloys ◽

10.1016/j.jma.2021.07.008 ◽

2021 ◽

Author(s):

Li Hu ◽

Mengwei Lang ◽

Laixin Shi ◽

Mingao Li ◽

Tao Zhou ◽

...

Keyword(s):

Finite Element ◽

Constitutive Model ◽

Finite Element Simulation ◽

Hot Deformation ◽

Deformation Behavior ◽

Simulation Method ◽

Hot Deformation Behavior ◽

Element Simulation

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Plastic Flow Stress and Constitutive Model for H96 Brass Alloy

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.782.130 ◽

2015 ◽

Vol 782 ◽

pp. 130-136 ◽

Cited By ~ 1

Author(s):

Ping Zhou ◽

Wei Guo Guo ◽

Hai Hui Wu

Keyword(s):

Flow Stress ◽

Constitutive Model ◽

Plastic Flow ◽

Split Hopkinson Pressure Bar ◽

Testing Machine ◽

Experimental Results ◽

Dynamic Strain ◽

Strain Rates ◽

Brass Alloy ◽

Plastic Flow Stress

To explore the thermo-mechanical response of H96 brass alloy, the quasi-static (universal-testing machine) and dynamic (the split Hopkinson pressure bar apparatus) uniaxial compression experiments have been performed under the temperatures from 293 K to 873 K and the strain rates from 0.001 s-1 to 6000 s-1, and the strains over 60% are obtained. Results show that, H96 brass alloy has strong strain hardening behavior, and it becomes weaker with the increasing temperature. In addition, this alloy is sensitive to strain rates; and, it has temperature sensitivity, the dynamic strain aging occurs at the temperature of 473 K and a quasi-static strain rate of 0.001 s-1. Based on the thermal activation dislocation mechanism, paralleled with the experimental results, a plastic flow constitutive model with the physical conception is developed. The model is suitable to predict the plastic flow stress at different temperatures and strain rates. According to comparing results, the model predictions are in good agreement with the experimental results.

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