Dynamic Recrystallization Softening Research Articles

Numerical Investigation of the Damage Effect on the Evolution of Adiabatic Shear Banding and Its Transition to Fracture during High-Speed Blanking of 304 Stainless Steel Sheets.

This paper investigates numerically the effect of damage evolution on adiabatic shear banding (ASB) formation and its transition to fracture during high-speed blanking of 304 stainless steel sheets. A structural-thermal-damage-coupled finite element (FE) analysis is developed in LS-DYNA considering the modified Johnson-Cook thermo-viscoplastic model for both plasticity flow rule and damage law, while further, a temperature-dependent fracture criterion is implemented by introducing a critical temperature. The modeling approach is initially validated against experimental data regarding the fracture profile and ASB width. Next, FE simulations are conducted to examine the effect of strain rate and temperature dependence on damage law, while the effect of damage coupling is also evaluated, aiming to highlight the connection between thermal and damage softening and attribute them a specific role regarding ASB formation and transition to fracture. Also, the influence of dynamic recrystallization (DRX) softening is studied macroscopically, while further, a parametric analysis of the Taylor-Quinney coefficient is conducted to highlight the effect of plastic work-to-internal heat conversion efficiency on ASB formation. The results revealed that the implementation of damage coupling reacts to reduced ASB width and provides an S-shaped fracture profile, while it also decreases the peak force and results in an earlier fracture. Both findings are enhanced when accounting further for DRX softening and a higher value of the Taylor-Quinney coefficient. Finally, the simulations indicated that thermal softening precedes damage softening, showing that the temperature rise is responsible for ASB initiation, while instead, damage evolution drives ASB propagation and fracture.

Elucidating the dual effect of vanadium microalloying on hot deformation behavior of high nitrogen martensitic stainless steel

Precipitates always have a complex effect on the hot work hardening and recrystallization softening of materials. In this work, the dual effect of V-microalloying on hot deformation behavior and microstructure evolution of high nitrogen martensitic stainless steel (HNMSS) was investigated by hot compression experiments, modeling study and microstructure characterization. The results showed that V-microalloying enhanced the flow stresses and activation energy of 0.2V steel due to the fine grain strengthening effect and the blocking effect of dynamic precipitation on dislocation movement and grain boundary migration. On the other hand, the recrystallization model and deformed microstructure indicated the more intense dynamic recrystallization (DRX) softening effect in 0.2V steel, inducing the faster decrease of flow stress after the peak stress. V-microalloying promoted the dynamic precipitation of HNMSS during hot deformation, which reduced the size and increased the number of precipitates in 0.2V steel. The fine precipitates hindered dislocation movement, promoted dislocation accumulation and entanglement, formed a particle deformation zone (PDZ) with high dislocation density and large orientation gradient, and then induced the occurrence of particle-stimulated nucleation (PSN). In addition, the dislocation cells evolved from dislocation entanglement were also favorable nucleation sites for DRX.

Microstructure and texture evolution during high-temperature compression of Al-Mg-Si-Zr-Mn alloy

The hot deformation behavior of an Al-Mg-Si-Zr-Mn alloy was investigated by performing uniaxial compression tests over a temperature range of 400–550 °C and strain-rate range of 0.001–1 s−1. A decline ratio map was generated and divided into three different domains to understand the correlation between the flow stress behavior and various microstructural softening mechanisms. In domain I (deformed at 400–500 °C and 1 s−1), work hardening was more predominant than dynamic recovery (DRV). In domain II (deformed at 400–550 °C and 0.1–0.01 s−1), the microstructure was more homogenous than that in domain I. DRV was the main softening mechanism, with a dynamic equilibrium between DRV and work hardening. Owing to the higher deformation temperature and lower strain rate in domain III (450–550 °C and a strain rate of 0.001 s−1), the deformed structure almost completely disappeared, and a large number of dynamic recrystallized grains were formed. The microstructure was dominated by a combination of DRV and dynamic recrystallization softening mechanisms. Under these conditions, the flow stress decreased significantly with increasing strain owing to the presence of 44% dynamic recrystallized grains and slight coarsening of dispersoids. Textural analysis revealed the presence of strong Goss {011} 〈100〉, moderately Rotated Cube {001} 〈110〉, and Copper {112} 〈111〉 components in domains I and II. In contrast, Goss and S textures were moderately developed when deformation was performed in domain III.

Thermal deformation behavior and microstructure evolution of Fe−8.5Mn−1.5Al light−weight medium manganese steel

In this paper, Fe−8.5Mn−1.5Al light−weight medium Mn steel is used as the research object, and the hot compression test is conducted by Gleeble−3500 thermal simulation tester. The dynamic reversion and dynamic recrystallization (DRX) processes are analyzed according to the true stress−strain curve; the θ−σ work−hardening rate curve is plotted by P−J double differential method to analyze the influence law between work−hardening and dynamic reversion and recrystallization softening effect of the material; the DRX critical strain model is established to analyze the influence law of deformation parameters on DRX; Based on the dynamic material model theory, the hot working diagram and three−dimensional power dissipation diagram are constructed, and the best hot working area is determined by combining the microstructure of the material. Finally, based on the above research content, a systematic overview of the dynamic softening effects of DRX and dynamic recovery (DRV) will be provided.

Subroutine Embedding and Finite Element Simulation of the Improved Constitutive Equation for Ti6Al4V during High-Speed Machining.

The Johnson-Cook (J-C) constitutive model is not suitable for Ti-6Al-4V alloy in the high-speed cutting finite element simulation, as it has no response dynamic recrystallization softening effect under heavy impact and high temperature. In this paper, an improved constitutive model considering the recrystallization effect was established, and the parameters were fitted with the data of flow stress-strain of the Split Hopkinson Pressure Bar (SHPB) test. The relevant theories of cutting finite element simulation were studied, such as nonlinear constitutive elastic-plastic deformation, strain state, and material yield. A subroutine that included the Recht shear failure instability criterion and the improved model was coded in Fortran and embedded in the finite element simulation software AdvantEdge FEM, along with the return mapping stress integration algorithm. The simulated stress of the improved model dropped dramatically from 460 MPa to 220 MPa when the temperature rises from 950 °C to 1000 °C, and its decline reached 46.7%, while the J-C model only decreased by 10%. Comparative studies indicate that the stress change of the improved constitutive simulation is closer to the SHPB test results than the J-C constitutive, and the new one is more suitable when it expresses the high temperature and heavy impact in the high-speed milling.

Elevated-temperature wear behavior of Ti6Al4V alloy: microstructural evolution and properties change in subsurfaces and mild-severe wear transition

Dry sliding wear behavior of Ti6Al4V alloy was studied at elevated temperatures of 50 °C–400 °C. The constituent phases and morphologies of worn surfaces were examined to evaluate the roles of oxide layers and wear mechanisms in mild-severe wear transition (M-SWT). Microstructural evolution and hardness change in subsurfaces were also investigated to reveal the most fundamental reason for M-SWT. The results showed that M-SWT happened via severe plastic deformation (SPD) within 20 °C–350 °C, while mild wear prevailed via a protective mechanically mixed layer (MML) containing multiple oxide phases at 400 °C. Large surface plastic deformation and frictional heat activated dynamic recrystallization (DRX) softening in subsurface, which resulted in M-SWT. The critical load for M-SWT presented an approximate linear relationship with testing temperature within 20 °C–250 °C, from which a critical temperature of 555.8 °C for M-SWT was obtained by linearly fitting method. It was thought as the critical temperature for DRX realization in surface layer, and it was utilized to calculate the transition loads at 300 °C and 350 °C.

The Effect of (Mg, Zn)12Ce Phase Content on the Microstructure and the Mechanical Properties of Mg-Zn-Ce-Zr Alloy.

The quantitative study of rare earth compounds is important for the improvement of existing magnesium alloy systems and the design of new magnesium alloys. In this paper, the effective separation of matrix and compound in Mg–Zn–Ce–Zr alloy was achieved by a low-temperature chemical phase separation technique. The mass fraction of the (Mg, Zn)12Ce compound was determined and the effect of the (Mg, Zn)12Ce phase content on the heat deformation organization and properties was investigated. The results show that the Mg–Zn–Ce compound in both the as-cast and the homogeneous alloys is (Mg, Zn)12Ce. (Mg, Zn)12Ce phase formation depends on the content and the ratio of Zn and Ce elements in the initial residual melt of the eutectic reaction. The Zn/Ce mass ratios below 2.5 give the highest compound contents for different Zn contents, 5.262 wt.% and 7.040 wt.%, respectively. The increase in the amount of the (Mg, Zn)12Ce phase can significantly reduce the critical conditions for dynamic recrystallization formation. Both the critical strain and the stress decrease with increasing rare earth content. The reduction of the critical conditions and the particle-promoted nucleation mechanism work together to increase the amount of dynamic recrystallization. In addition, it was found that alloys with 6 wt.% Zn elements tend to undergo a dynamic recrystallization softening mechanism, while alloys with 3 wt.% Zn elements tend to undergo a dynamic reversion softening mechanism.

Masking Effect of LPSO Structure Phase on Wear Transition in Mg97Zn1Y2 Alloy

Room- and elevated-temperature wear tests were conducted using a pin-on-disk testing machine to study wear behavior of Mg97Zn1Y2 alloy and role of long-period-stacking-ordered (LPSO) structure phase in mild–severe wear transition (SWT). Variation of wear rate exhibited a three-stage characteristic with load at various test temperatures, i.e., a gradual increasing stage, a slightly higher plateau stage, and a rapid rising stage. The wear mechanisms in the three stages were identified using scanning electron microscope (SEM), from which the first stage was confirmed as mild wear, and the other two stages were verified as severe wear. The interdendritic LPSO structure phase was elongated into strips along the sliding direction with Mg matrix deformation in the subsurface, plate-like LPSO structure phase precipitated at elevated temperatures of 150 and 200 °C. The fiber enhancement effect and precipitation effect of LPSO structure phase resulted in a little difference in wear rate between the first and second stages, i.e., a masking effect on SWT. Microstructure and microhardness were examined in the subsurfaces, from which the mechanism for SWT was confirmed to be dynamic recrystallization (DRX) softening. There is an apparently linear correlation between the critical load for SWT and test temperature, indicating that SWT is governed by a common critical DRX temperature.

Hot Tensile Deformation Behavior of Mg-4Li-1Al-0.5Y Alloy

The microstructure evolution and deformation mechanism of the as-extruded-annealed Mg-4Li-1Al-0.5Y alloy (denoted as LAY410) were investigated during the hot tensile deformation at the temperatures between 150°C and 300°C with strains from 8 × 10−5 s−1 to 1.6 × 10−3 s−1. The results show that when the strain rate decreases and/or the deformation temperature increases, the peak stress of the alloy gradually decreases, and the elongations to fracture gradually increases. The true stress–strain curves show typical dynamic recrystallization (DRX) softening characteristics. It is observed that the microstructure in the magnesium (Mg) alloy deformed at 150°C is mainly composed of the deformed grains and a few recrystallized grains. The microstructures in the Mg alloy deformed at 200°C consisted of substructures and a slightly increasing number of dynamic recrystallized grains. When the deformation temperature reaches 250°C, the number of recrystallized grains increases significantly, and the microstructures are dominated by recrystallized grains. Moreover, through theoretical calculation and result analysis, the activation energy was about 99.3 kJ/mol, and the hot tensile deformation mechanism was the alternate coordinated deformation mechanism among grain boundary slip (GBS), intragranular slip, and DRX.

Advances in formation mechanisms and multiscale simulations of adiabatic shear bands in metallic materials

<p indent=0mm>Adiabatic shear bands (ASBs) become an important failure mechanism when the ductile metallic materials are loaded under the dynamic impact. This thermoplastic instability behavior occurring in such a narrow band under the coupling actions of force and thermal effect easily causes a rapid propagation of crack inside the ASB or along its boundary, subsequently leading to a sudden failure. The extremely small scale of adiabatic shear bands in space and time has brought great challenges to experimental investigations. For this reason, scholars have not obtained a comprehensive understanding of this unique mechanical behavior, but a lot of research work has already been done and many breakthroughs have been made in this research field. In the experimental studies, the applications of high-speed and high-resolution testing techniques make people observe the whole process of initiation and propagation of the ASBs more clearly, and further recognize the role of different influencing factors in the emergence of ASBs, more specifically, the causal relationship between the adiabatic temperature rising and plastic localization. Based on a large number of experimental results, scholars have summarized a variety of mechanical explanations in recent years to reveal the formation mechanism of adiabatic shear instability behavior. Moreover, in the aspect of numerical analysis, the scholars have already put forward many kinds of modelling and simulation methods to help discern the formation process of ASB. In addition to the modelling method at a macro scale, multiscale simulation methods consider different kinds of microscopic mechanisms in their constitutive relations. As such, the influences of different microscopic variables on the dynamic mechanical behavior can be analyzed independently via multiscale simulations, which can greatly promote the comprehension of formation mechanisms of adiabatic shear bands. In this review, the latest investigation advances on adiabatic shear instability behavior of the research group from impact dynamics and engineering application laboratory in Northwestern Polytechnical University, as well as a number of published results of other scholars, focusing on the formation mechanisms of ASBs in the metallic materials with different microscopic characteristics, are summarized. Firstly, the most classical thermal softening theory is discussed, and the latest measurement results revisiting the causal relationship between adiabatic temperature rise and localized deformation are reviewed. Then we briefly introduce some other softening mechanisms proposed based on the microstructure characteristics of metallic materials, including the geometric softening theory and dynamic recrystallization softening mechanism. Based on these above instability mechanisms, many simulation models are constructed to reproduce the formation process of ASBs. Therefore, we also systematically elaborate on the simulation studies on adiabatic shear instability behavior via multiscale simulation methods and track their respective progress. Besides the traditional modelling and finite element method at the macro scale, more simulations carried out at the meso/micro scales to reveal the physical essence of this behavior in recent years are stated, such as the crystal plasticity finite element method, phase filed simulation, discrete dislocation dynamics method and even atomistic simulations. Finally, we discuss the problems existing in this research field and future research focuses for the adiabatic shearing localizations.

A Flow Stress Model of 300M Steel for Isothermal Tension.

To investigate the effect of hot working parameters on the flow behavior of 300M steel under tension, hot uniaxial tensile tests were implemented under different temperatures (950 °C, 1000 °C, 1050 °C, 1100 °C, 1150 °C) and strain rates (0.01 s−1, 0.1 s−1, 1 s−1, 10 s−1). Compared with uniaxial compression, the tensile flow stress was 29.1% higher because dynamic recrystallization softening was less sufficient in the tensile stress state. The ultimate elongation of 300M steel increased with the decrease of temperature and the increase of strain rate. To eliminate the influence of sample necking on stress-strain relationship, both the stress and the strain were calibrated using the cross-sectional area of the neck zone. A constitutive model for tensile deformation was established based on the modified Arrhenius model, in which the model parameters (n, α, Q, ln(A)) were described as a function of strain. The average deviation was 6.81 MPa (6.23%), showing good accuracy of the constitutive model.

High strain rate compression deformation mechanism and constitutive equation of fine grained Mg–7Gd–5Y–1.2Nd–0.5Zr alloy at different temperatures

Dynamic compression experiments of fine grained Mg–7Gd–5Y–1.2Nd–0.5Zr alloy were measured by the split-Hopkinson pressure bar test at the strain rates in the range 1000–2000 s−1 and the temperature range 293–573 K along the transverse direction. The microstructure of the alloy was characterized by electron back-scattering diffraction and transmission electron microscopy. The results showed that the deformation hardening mechanisms dominated by pyramidal <c + a> slip and assisted by many mechanisms such as tension twinning, while the deformation softening mechanism just dominated by a partial dynamic recrystallization at the grain boundaries. During the entire deformation process at different temperatures, softening was found as the only accompanying mechanism of hardening. Even at 573 K, the fully recrystallized structure was not achieved, and the hardening mechanism was always dominant until they tend to balance. Based on these deformation mechanisms, especially the continuous attenuation mechanism of dynamic recrystallization softening associated with hardening, the Johnson–Cook model was modified, and a unified constitutive equation for deformation under high strain rate at different temperatures was constructed. The resulted obtained by this equation were in good agreement with the experimental results.

“Self-sharpening” tungsten high-entropy alloy

“Self-sharpening”, a material maintaining its acute head shape during penetration, is highly desirable in a wide range of engineering applications. However, it remains a great challenge to make it occur in conventional single-principal-element alloys. Here, we develop a new chemical-disordered multi-phase tungsten high-entropy alloy that exhibits outstanding self-sharpening capability, in sharp contrast to conventional tungsten alloys only showing mushrooming. This alloy consists of a BCC dendrite phase and a rhombohedral μ phase embedded in the continuous FCC matrix, and such a unique microstructure leads to a 10–20% better penetration performance than conventional tungsten heavy alloys. We show that emergence of the self-sharpening is triggered by the ultrastrong μ phase stimulated dynamic recrystallization softening mediated shear banding. This study sheds light on the origin of self-sharpening and might open new opportunities for developing high-performance penetrator materials.

Study on constitutive model and dynamic recrystallization softening behavior of AZ80A magnesium alloy

The microstructures of as-cast AZ80A magnesium alloy before and after homogenization treatment were studied. The flow behaviors of the homogenized alloy under different deformation conditions were studied by isothermal compression tests. Based on the flow stress-strain curves of the homogenized alloy, the constitutive model was established by the strain compensation method. The strain rate sensitivity index maps with different strains were constructed to quantify the dynamic recrystallization softening behavior of the homogenized alloy. Based on this, the influence of deformation temperature and strain rate on strain rate sensitivity index and dynamic recrystallization microstructure evolution were studied. The results show that both increasing homogenization temperature and holding time are beneficial for the β-phases to dissolve and alloying elements to diffuse. It is concluded that the proper homogenizing parameter of as-cast AZ80A magnesium alloy is 683 K for 20 h. Both the increase of deformation temperature and the decrease of strain rate are beneficial to the increase of strain rate sensitivity index. The region with an index greater than 0.22 corresponds to dynamic recrystallization softening zone and has good deformation properties.

Elevated-Temperature Wear Characteristics and Mild-Severe Wear Transition in the Mg–10.1Gd–1.4Y–0.4Zr Alloy

Abstract Dry sliding wear characteristics of the as-cast Mg–10.1Gd–1.4Y–0.4Zr alloy were investigated at 3.0 m/s within a temperature range of 20–200 °C on a pin-on-disc type wear testing machine. Wear rates were acquired and plotted against load at each test temperature. There existed a turning point on the wear rate versus load curve at each test temperature; it corresponded to the mild-severe wear transition. The wear mechanisms were confirmed through morphological and compositional analysis of worn surfaces. An elevated-temperature wear mechanism transition map was drawn, in which mild and severe wear regions were indicated. The differences in microstructure as well as microhardness in subsurfaces were compared between samples worn in the two different regions. The dynamic recrystallization (DRX) softening of the surface material was found to be responsible for mild-severe wear transition. An approximately linear relationship was found between the transition load and test temperature, suggesting that mild-severe wear transition of the alloy still follows a surface temperature criterion even at elevated temperatures. The critical surface temperature is thought of to be the DRX temperature of the alloy. It is approximately 279.3 °C based on the linearly fitting analysis of the transition load versus test temperature.

Flow behaviour constitutive model of CuCrZr alloy and 35CrMo steel based on dynamic recrystallization softening effect under elevated temperature

In order to study the effect of dynamic recrystallization on the metal flow behavior during thermal deformation, the elevated temperature compression experiments of CuCrZr alloy and 35CrMo steel are carried out using Gleeble-3810 thermal simulator. It is proved that the samples underwent obvious dynamic recrystallization behavior during thermal deformation by microstructure observation of deformed specimens. The size of recrystallized grains increases as the temperature improved and the strain rate decreased. Meanwhile, the net softening rate caused by dynamic recrystallization is determined based on the stress-dislocation relationship. It can be found that the value of net softening rate increases quadratically as the Z parameter decreases, and the dynamic recrystallization net softening rate of CuCrZr alloy and 35CrMo steel are calculated to be 21.9% and 29.8%, respectively. Based on the dynamic recrystallization softening effect proposed, the novel elevated temperature flow constitutive models of two different alloys are proposed, and the related parameters are well defined and solved in detail. The predicted values of the obtained models are agreed well with the experimental values.

A Dynamic Recrystallization (DRX) Constitutive Model for Elevated Temperature Flow Behavior of Cu-0.5Cr-0.1Zr Alloy

In order to obtain the high-temperature flow behavior of Cu-0.5Cr-0.1Zr alloy more accurately, the hot compression test of Cu-0.5Cr-0.1Zr alloy was performed at the strain rates from 0.001 to 1.0 s−1 and the deformation temperatures from 600 to 750 °C on a Gleeble-3800 thermo-simulation machine. The results show that the high-temperature flow stress and dynamic recrystallization behavior of Cu-0.5Cr-0.1Zr alloy are affected by strain rate and temperature. The peak stress is obvious under the condition of high temperature and low strain rate, and the flow stress curve shows a clear dynamic recrystallization phenomenon. On the contrary, there is no obvious peak stress at the low temperature and high strain rate, and dynamic softening behavior is mainly based on dynamic recovery. The high-temperature flow stress of Cu-0.5Cr-0.1Zr alloy is expressed as a result of multiple stress actions, such as work hardening, dynamic recovery softening, and dynamic recrystallization softening. The thermal deformation activation energy of this alloy can be calculated as 244.94 kJ/mol. The relationship between the critical stress and the critical strain of dynamic recrystallization and the Z parameter was established through the cubic linear fitting of the work hardening rate curve. Based on the stress–dislocation relation and kinetics of dynamic recrystallization, the constitutive equations before and after critical strain of Cu-0.5Cr-0.1Zr alloy were developed. The predicted stresses of the established DRX constitutive model agree well with the experimental stresses.

MPM simulations of high-speed machining of Ti6Al4V titanium alloy considering dynamic recrystallization phenomenon and thermal conductivity

• MPM has been used to study high-speed machining of Ti6A14V titanium alloy. • Recrystallization phenomenon and thermal conductivity have been considered. • Three modified Johnson−Cook constitutive models for Ti6A14V titanium alloy have been adopted. Ti6Al4V titanium alloy is often used in the aircraft industry due to its good strength and toughness etc. However, it is very difficult to simulate high speed machining of titanium alloy using the finite element method (FEM). The reason is that the high speed, large deformation and high strain rate of metal material at high temperature etc. will lead to the element distortions and other numerical difficulties. In contrast with FEM, material point method (MPM) has the advantage of simulating extreme large deformation, fracture and impact problems. Therefore, it is specially suitable for dealing with high speed cutting process. In many existing researches about the high speed cutting process using Johnson−Cook constitutive model, the material dynamic recrystallization softening effect under high pressure and high temperature has not been considered. For this, three modified Johnson−Cook constitutive models for Ti6Al4V titanium alloy are adopted and the parameters for these models were obtained by the split Hopkinson pressure bar (SHPB) test considering the critical strain values, high-temperature range and dynamic recrystallization phenomenon. Furthermore, to ensure the numerical accuracy, the transient heat conduction algorithm is employed in MPM implementation. Finally, comparison and discussion are carried out between the experimental and the simulation data, which show that the high speed cutting process can be better simulated using the modified Johnson−Cook constitutive models.

Hot deformation behavior of AZ80 magnesium alloy towards optimization of its hot workability

The flow stress curves of AZ80 magnesium alloy were obtained by isothermal compression experiment conducted at 275–400°C and 0.001–1s−1. Work-hardening behavior and dynamic recrystallization leading softening behavior in hot deformation process were described by Z parameter. Deformation activation energy at different strains was calculated by constitutive equation and power dissipation map at different strains was constructed. Combining the Z parameter and the power dissipation efficiency, the effect of different deformation temperatures and strain rates on deformation mechanism and microstructure were investigated, especially the effect of dynamic recrystallization on grain refinement was analyzed in detail. The results showed that with increasing deformation temperature and decreasing strain rate, the Z parameters decreased and the power dissipation efficiency increased, which was contributed to the occurrence of dynamic recrystallization softening. A decreasing tendency of deformation activation energy with increasing strains was observed. Furthermore, the optimum hot processing domain for fine grain microstructure was determined as 283–310°C and 0.001–0.0017s−1 corresponding to a power dissipation value of 0.41, where the fine grain structure with average grain size of 8μm could be generated. The results were applied to the workability optimization of typical component in isothermal forging experiment, which could obtain fine grain structure with average grain size of 5μm and significantly improve strength of the component.

Comparing predictions from constitutive equations and artificial neural network model of compressive behavior in carbon nanotube–aluminum reinforced ZA27 composites

Abstract Hybrid carbon nanotube–aluminum reinforced ZA27 composites under hot compressive forces were investigated in the temperature range of 473 – 523 K with strain rates of 0.01 – 10 s−1. From the experimental data, the flow stress curves for increasing strain exhibit typical flow behavior associated with dynamic recrystallization softening. A comparison of predictions from an artificial neural network model and the constitutive equations to describe the hot compressive behavior was performed. Relative errors varied from −4.14 % to 6.75 % for the artificial neural network model and from −15.93 % to 17.29 % using the constitutive equations. The results indicate that the artificial neural network model was more accurate and efficient in predicting hot compressive behavior.