Microstructural based models for bcc and fcc metals with temperature and strain rate dependency

Microstructural physical based constitutive models are developed in this work in order to characterize the deformation behavior of body centered cubic (bcc) and face centered cubic (fcc) metals under different strain rates and temperatures. The concept of thermal activation energy as well as the dislocations interaction mechanisms is used in the derivation procedure taking into consideration the effect of the mobile dislocation density evolution on the flow stress of the deformed material. The derivation of the Zerilli–Armstrong (Z–A) physical based model for both (bcc) and (fcc) metals is investigated and a number of modifications are incorporated such as the evolution of mobile dislocation density. The authors conclude that in spite of the physical basis used in the derivation of the Z–A model, its parameters can not be interpreted physically since the approximation ln(1 + x) ≈ x is used in the final step of the derivation. This expansion, however, is valid only for values x ≪ 1.0 which is not the case at high strain rates and temperatures. New bcc and fcc relations for the flow stress are therefore suggested and derived using the exact results of the expansion of ln(1 + x). Several experimental data obtained by different authors for tantalum (Ta), niobium (Nb), molybdenum, (Mo), vanadium (V) (bcc metals) and Oxygen Free High Conductivity (OFHC) Copper (Cu) (an fcc metal) are used in evaluating the proposed models. A good agreement between the experimental results and the proposed models are obtained. Moreover, the predicted results show that the assumption of ignoring the generation of dislocation density during the plastic deformation is not appropriate particularly in the case of high strain rates and temperatures. This causes the values of the thermal stresses to be overestimated. Numerical identification for the physical quantities used in the definition of the model parameters is also presented.     

Effect of Nb and C on the hot flow behavior of Nb microalloyed steels

The compressive deformation behaviors of a C–Mn steel (0.36C–1.42Mn) and two Nb microalloyed steels (0.35C–1.41Mn–0.044Nb and 0.055C–1.42Mn–0.036Nb) were investigated at the temperatures from 900 °C to 1100 °C and strain rates from 0.005 s⁻¹ to 10 s⁻¹ on Gleeble-1500 thermo-mechanical simulator. It was found that the flow stress of the C–Mn steel is the lowest among the experimental steels, indicating that Nb microalloying in HSLA steels can effectively increase the hot deformation flow stress, and the 0.055C–1.42Mn–0.036Nb steel has a higher flow stress than that of the 0.35C–1.41Mn–0.044Nb steel, indicating that C addition generates a softening effect. The flow stress constitutive equations of hot deformation were developed for the experimental steels, the activation energy Q about 360 kJ/mol for the 0.055C–1.42Mn–0.036Nb steel was higher than that for the 0.35C–1.41Mn–0.044Nb steel (347 kJ/mol) and the C–Mn steel (278 kJ/mol). Characteristic points of flow stress for the three steels were analyzed. The results showed that Nb addition can effectively increase the peak strain and the steady state strain of steels, thus delay distinctly the occurrence of dynamic recrystallization, while C addition can reduce the peak strain and the steady state strain of Nb microalloyed steels, thus promote the occurrence of dynamic recrystallization.     

Relationship between mechanical properties and microstructural response of 6061-T6 aluminum alloy impacted at elevated temperatures

The high temperature impact properties and microstructural evolution of 6061-T6 aluminum alloy are investigated at temperatures ranging from 100 to 350 °C and strain rates ranging from 1 × 10³ to 5 × 10³ s⁻¹ using a compressive split-Hopkinson pressure bar (SHPB) system. It is found that the flow response and microstructural characteristics of 6061-T6 aluminum alloy are significantly dependent on the strain rate and temperature. The flow stress and strain rate sensitivity increase with increasing strain rate or decreasing temperature. Moreover, the temperature sensitivity increases with both increasing strain rate and increasing temperature. The flow stress–strain response of the present 6061-T6 alloy specimens can be adequately described by the Zerilli–Armstrong fcc model. The grain size and dislocation cell size increase significantly with a decreasing strain rate or an increasing temperature. The higher flow stress is the result of a smaller grain size and smaller dislocation cell size. The stacking fault energy of the deformed specimens has a value of 145.78 mJ/m².     

Effects of initial grain size on hot deformation behavior of commercial pure aluminum

The effects of initial grain size of commercial pure aluminum on hot deformation behavior were investigated using hot compression tests. The hot compression tests were carried out on the pure aluminum samples with the initial grain sizes of 50, 150 and 450 μm using various strains, strain rates and different deformation temperatures. It was found that the hot deformation behavior of used material was sensitive to deformation conditions and initial microstructure. Results indicate that the initial grain size has significant effect on the flow stress. Flow stress decreases when the grain size decreases from 450 to 50 μm and when strain rate is lower than 0.05 s⁻¹. This procedure is reversed at strain rate of 0.5 s⁻¹. Furthermore, effects of other parameters like the strain rates and deformation temperatures on the flow stresses and hardening rates were investigated. It was also found that the inhomogeneity of microstructure distribution at different positions of the deformed specimens depended on the amount of deformation concentration at particular points and other processing parameters such as initial grain sizes, strain rates and deformation temperatures. In addition the geometric dynamic recrystallization (GDRX) was observed in the specimens highly strained (0.7) at elevated temperature (500 °C) using polarized light microscope and sensitive tint (PLM + ST).     

Laser shock peening effect on the dislocation transitions and grain refinement of Al–Mg–Si alloy

This paper systematically investigates the effect of laser shock peening without coating parameters on the microstructural evolution, and dislocation configurations induced by ultra-high plastic strains and strain rates. Based on an analysis of optical microscopy, polarized light microscopy, transmission electron microscopy observations and residual stress analysis, the significant influence of laser shock peening parameters due to the effect of plasma generation and shock wave propagation has been confirmed. Although the optical microscopy results revealed no significant microstructural changes after laser shock peening, i.e. no heat effect zone and differences in the distribution of second-phase particles, expressive influence of laser treatment parameters on the laser shock induced craters was confirmed. Moreover, polarized light microscopy results have confirmed the existence of well-defined longish grains up to 455 μm in length in the centre of the plate due to the rolling effect, and randomly oriented smaller grains (20 μm × 50 μm) in the surface due to the static recrystallization effect. Laser shock peening is reflected in an exceptional increase in dislocation density with various configurations, i.e. dislocation lines, dislocation cells, dislocation tangles, and the formation of dense dislocation walls. More importantly, the microstructure is considerably refined due to the effect of strain deformations induced by laser shock peening process. The results have confirmed that dense dislocation structures during ultra-high plastic deformation with the addition of shear bands producing ultra-fine (60–200 nm) and nano-grains (20–50 nm). Furthermore, dislocation density was increased by a factor of 2.5 compared to the untreated material (29 × 10¹³ m^− 2 vs. 12 × 10¹³ m^− 2).     

Dependence of dynamic strain ageing on strain amplitudes during the low-cycle fatigue of TP347H austenitic stainless steel at 550 °C

Low-cycle fatigue (LCF) tests are carried out on TP347H stainless steel at a strain rate of 8 × 10⁻³ s⁻¹ with total strain amplitudes (Δε_t/2) of ±0.4% and ±1.0%, at room temperature (RT) and 550 °C. It is found that the stress responses and dislocation structures under cyclic loading strongly depend on the value of strain amplitude at 550 °C. Compared with those at the same strain amplitude at RT, the material shows a rapid strain softening, and finally attains a stabilized state at Δε_t/2 = ±0.4% and 550 °C, but the one presents an anomalous behavior, i.e., first a rapid hardening to the maximum stress, followed by a reducing softening at Δε_t/2 = ±1.0% and 550 °C. More cells resulting from dislocation cross-slip and planar structures due to dynamic strain ageing (DSA) restricting cross-slip develop at low strain amplitude of ±0.4% at the first cycle. However, there are more complicated dislocation structures, such as cells, elongated cells, walls/channels and planar structures at Δε_t/2 = ±1.0%. The observations of scanning electron microscopy (SEM) and transmission electron microscopy (TEM) exclude the effects of martensitic transformation, creep, oxidation, and precipitations on these stress responses and microstructure evolutions, which result from DSA appearing at 550 °C.     

Effect of strain rate on low cycle fatigue of 316LN stainless steel with varying nitrogen content: Part-I cyclic deformation behavior

The effect of strain rate and nitrogen content on cyclic deformation and substructural changes in 316LN stainless steel is investigated at temperatures 773, 823 and 873 K. Dynamic strain aging (DSA) and/or thermal-recovery processes are observed to control cyclic deformation, and the regimes of their predominance are mapped. An increase in nitrogen content and DSA enhanced cyclic stress and are found to offset thermal-recovery induced cyclic strength reduction. In addition, strain localization in the form of slip-bands impinging on grain boundary is observed. The predominance of thermal-recovery over DSA manifested as dislocation-poor channels, dislocation cells within and in-between planar slip-bands.     

Impact and fracture response of sintered 316L stainless steel subjected to high strain rate loading

This paper describes the use of a material testing system (MTS) and a compressive split-Hopkinson bar to investigate the impact behaviour of sintered 316L stainless steel at strain rates ranging from 10^− 3 s^− 1 to 7.5 × 10³ s^− 1. It is found that the flow stress–strain response of the sintered 316L stainless steel depends strongly on the applied strain rate. The rate of work hardening and the strain rate sensitivity change significantly as the strain rate increases. The flow behaviour of the sintered 316L stainless steel can be accurately predicted using a constitutive law based on Gurson's yield criterion and the flow rule of Khan, Huang and Liang (KHL). Microstructural observations reveal that the degree of localized grain deformation increases at higher strain rates. However, the pore density and the grain size vary as a reversible function of the strain rate. Impacts at strain rates higher than 5.6 × 10³ s^− 1 are found to induce adiabatic shear bands in the specimens. These specimens subsequently fail as a result of crack propagation along the dominant band. The fracture surfaces of the failed specimens are characterized by dimple-like structures, which are indicative of ductile failure. The depth and the density of these dimples are found to decrease with increasing strain rate. This observation indicates a reduction in the fracture resistance and is consistent with the observed macroscopic flow stress–strain response.     

Metallurgical aspects on the fatigue of solution-annealed austenitic high interstitial steels

Austenitic stainless steels have been used for over 100 years for their combination of strength and ductility. In order to further improve the mechanical and chemical properties of austenitic high nitrogen steels (AHNS) were developed. Ni reduces the solubility of N and, therefore, was substituted by Mn in order to allow for up to 1 weight-% N to be alloyed. AHNS show an even higher strength for the solution annealed state, which can be increased further by cold working. Unfortunately the endurance limit did not follow this trend as it is known to for cold-worked Ni-containing steels. The solution annealed Ni-containing austenites allow for wavy slip and the generation of dislocation cells while the Mn-alloyed AHNS only show planar slip with twins and stacking faults. While the stacking fault energy was thought to be the main reason for planar slip, early results showed that there must be other near-field effects. The density of free electrons, which is mainly influenced by the sum and the ratio of C and N, might be responsible. Strain-controlled fatigue tests were carried out in CrMn-alloyed austenitic steels with different sums (C + N: 0.65–1.2) and ratios (C/N: 0.13–∞) of C and N. Manson–Coffin analyses revealed distinct differences in the fatigue behaviour to CrNi-alloyed C + N steels investigated earlier. This contribution presents these differences and discusses them in relation to microstructural characteristics as well their alterations under cyclic loading.     

Study of the processing map and hot deformation behavior of a Cu-bearing 317LN austenitic stainless steel

The hot-working behavior of a Cu-bearing 317LN austenitic stainless steel (317LN–Cu) was investigated in the 950–1150 °C temperature and 0.01–10 s^− 1strain rate range, respectively. The effects of different deformation parameters and optimum hot-working window were respectively characterized through analyzing flow stress curves, constitutive equations, processing maps and microstructures. The critical strain for dynamic recrystallization (DRX) was determined by the inflection point on θ-σ and −∂θ/∂σ-σ curves. The peak stress was found to increase with decrease in temperature and increase in strain rate. Typical signs of DRX over a wide range of temperatures and strain rates were observed on the flow stress curves. The power dissipation maps in the strain range of 0.1–0.4 were basically similar, indicating the insignificant effect of strain on the power dissipation maps of 317LN–Cu. However, the instability maps showed strong strain sensitivity with increasing strain, which was attributed to the flow localization. The optimum hot-working window for 317LN–Cu was obtained in the temperature range 1100–1120 °C and strain rate range 0.01–0.018 s^− 1, with a peak efficiency of 38%. Microstructural analysis revealed fine and homogenized recrystallized grains in this domain.     

Effect of strain amplitude on the low-cycle fatigue behavior of a new Fe–15Mn–10Cr–8Ni–4Si seismic damping alloy

The low-cycle fatigue (LCF) properties and post-fatigue microstructure of a Fe–15Mn–10Cr–8Ni–4Si austenitic alloy were investigated under an axial strain control mode with total strain amplitudes, Δε_t/2, ranging from 2.5 × 10⁻³ to 2 × 10⁻². The fatigue resistance of the alloy was described by Coffin–Manson’s and Basquin’s relationships, and the corresponding fatigue parameters were evaluated. In addition, the Masing behavior, which is associated with a constant deformation mode during fatigue, was revealed at the examined strain amplitudes. Microstructural observations of the fatigue fractured samples showed that the strain induced ε-martensitic transformation accompanied by a planar slip of the Shockley partial dislocations in the austenite is the main deformation mode controlling the fatigue behavior of the studied alloy at Δε_t/2 < 2 × 10⁻². However, at Δε_t/2 = 2 × 10⁻², the formation of a cell structure was found in the austenite in addition to ε-martensitic transformation. The LCF resistance of the alloy was compared with conventional Cr–Ni austenitic stainless steels, ferrous base TRIP and TWIP steels and low yield point damping steels. It was found that at the studied strain amplitudes the alloy possessed a higher LCF resistance compared to conventional Fe-base alloys and steels. Remarkably, the fatigue ductility coefficient, ε_f′, of the studied alloy is 1.3–6 times higher than that of the stainless steels because of a cyclic deformation-induced ε-martensitic transformation. The results showed that the ε-martensitic transformation that occurred in the studied alloy during LCF is the main reason for the improved LCF resistance.     

Workability characteristics and mechanical behavior modeling of severely deformed pure titanium at high temperatures

In the present study, compression tests were performed at temperatures of 600–900 °C and at strain rates of 0.001–0.1 s⁻¹ to study the deformation and workability characteristics of commercially pure titanium after severe plastic deformation (SPD). It was found that the effects of temperature and strain rate are significant in dictating the steady state flow stress levels and the strain values corresponding to peak flow stress. The strain rate sensitivity (m) during hot compression of severely deformed Ti was shown to be strongly temperature dependent, where m increased with the increase in deformation temperature up to 800 °C. High temperature workability was analyzed based on the flow localization parameter (FLP). According to the FLP values, deformation at and below 700 °C is prone to flow localization. The flow behavior was predicted using Arrhenius type and dislocation density based models. The validities of the models were demonstrated with reasonable agreement in comparison to the experimental stress–strain responses.     

Study on hot workability and optimization of process parameters of a modified 310 austenitic stainless steel using processing maps

To investigate the optimized hot deformation parameters of a modified 310 austenitic stainless steel, the hot compression tests were performed using a Gleeble 3500 thermal simulator. The hot deformation behavior and hot workability characteristics were investigated in a temperature range of 800–1100 °C and a strain rate range of 0.1–10 s⁻¹. The hot processing maps of the tested steel were developed based on the dynamic material model (DMM), from which the safe deformation regions and instable deformation regions were determined. The corresponding microstructural and hardness evolutions during deformation were analyzed in detail. It was found that the deformation in the safe regions was beneficial to dynamic recovery (DRY) and dynamic recrystallization (DRX), while the deformation in unstable region would lead to flow instability, kink boundaries and grain growth. Near 950 °C, the energy dissipation rates were unusually lower, and the hardness of the deformed sample exhibited a significant increase, as a result of strain-induced precipitation. Coupled with the microstructure analysis and processing map technology, the workability map was schematically plotted and the optimal working conditions were determined. Such conditions were: temperatures in the range of 1075–1100 °C and strain rates in the range of 0.5–1.7 s⁻¹. These conditions are critical to attain an excellent homogeneous microstructure with fine grains after deformation for the modified 310 austenitic stainless steel.     

Anisotropic and temperature effects on mechanical properties of copper nanowires under tensile loading

Atomistic simulations are used to investigate the mechanical properties of copper nanowires (NWs) along 〈1 0 0〉, 〈1 1 0〉 and 〈1 1 1〉 crystallographic orientations under tensile loading at different temperatures. The inter-atomic interactions are represented by employing embedded-atom potential. To identify the defects evolution and deformation mechanism, a centrosymmetry parameter is defined and implemented in the self-developed program. The simulations show that Cu NWs in different crystallographic orientations behave differently in elongation deformations. The stress–strain responses are followed by a particular discussion on yield mechanism of NWs from the standpoint of dislocation moving. Generally, the study on the incipient plastic deformation will be helpful to further understanding of the mechanical properties of nanomaterials. In addition, the Young’s modulus decreased linearly with the increase of temperature. The crystal structure is less stable at elevated temperatures.     

Investigation of stress corrosion cracks in a UNS S32750 superduplex stainless steel

Duplex and superduplex stainless steels are corrosion resistant alloys with many uses in chemical and petrochemical industries. It is generally accepted that these alloys present stress corrosion resistance superior to austenitic grades, but it does not mean that they are immune to this type of failure. Under severe conditions of temperature, stress, low pH, high chloride and H₂S contents superduplex steels may fail environmentally assisted cracking (EAC). In this work, superduplex UNS S32750 steel specimens were subjected to critical environmental conditions which produced stress corrosion cracks. In the first experiment the material was tested by slow strain rate tensile tests at 80 °C in a solution with 115,000 ppm of chloride, H₂S partial pressure of 6.75 psia, and pH = 3.0. In a second experiment the material was subjected to four bend beam test in a solution similar to experiment 1, but with a H₂S partial pressure of 30.0 psia. Finally, a third test was conducted in a bend plate of superduplex steel subjected to MgCl₂ saturated solution at 154 °C. The cracks produced in the three experiments showed quite different features, which were investigated by optical and scanning electron microscopy.     

Effect of the thermal cycle on the hot ductility and fracture mechanisms of a C–Mn steel

Transverse cracking on the surface of continuously cast steel products has been one of the main problems of this stage in steelmaking for many years. The incidence of this problem has been found in microalloyed steels as well as in some plain carbon steels containing residual elements. In this work, the hot ductility and fracture mechanisms of a C–Mn steel containing 0.6%Cu and 0.053%Sn as residual elements have been evaluated. To simulate the thermo-mechanical conditions of the straightening operation, tensile tests were carried out at temperatures ranging from 700 to 1100 °C with an initial strain rate of 5 × 10⁻³ s⁻¹. Specimens were subjected to three different reheating temperatures prior to the hot ductility test, including 1100 °C, 1330 °C and melting. After each test, the reduction in area of the samples tested to fracture was used as a measure of the hot ductility. The fracture surfaces were then examined by scanning electron microscopy. The widest and deepest ductility trough was obtained for the specimens tested after melting; for these conditions brittle fractures are interdendritic showing very low ductility. After reheating at 1330 °C, fracture features showed intergranular fracture combined with some plastic deformation corresponding to the test temperature. Reheating at 1100 °C produced a finer microstructure and the fracture features showed a mixture of intergranular with some interdendritic features. Also, ductile behaviours were associated with void coalescence. The different results obtained depending on the thermal cycle can be attributed to the presence of the residual elements in the steel through different segregation and precipitation patterns.     

Influence of stress triaxiality and strain rate on the failure behavior of a dual-phase DP780 steel

To better understand the in-service mechanical behavior of advanced high-strength steels, the influence of stress triaxiality and strain rate on the failure behavior of a dual-phase (DP) 780 steel sheet was investigated. Three flat, notched mini-tensile geometries with varying notch severities and initial stress triaxialities of 0.36, 0.45, and 0.74 were considered in the experiments. Miniature specimens were adopted to facilitate high strain rate testing in addition to quasi-static experiments. Tensile tests were conducted at strain rates of 0.001, 0.01, 0.1, 1, 10, and 100 s⁻¹ for all three notched geometries and compared to mini-tensile uniaxial samples. Additional tests at a strain rate of 1500 s⁻¹ were performed using a tensile split Hopkinson bar apparatus. The results showed that the stress–strain response of the DP780 steel exhibited mainly positive strain rate sensitivity for all geometries, with mild negative strain rate sensitivity up to 0.1 s⁻¹ for the uniaxial specimens. The strain at failure was observed to decrease with strain rate at low strain rates of 0.001–0.1 s⁻¹; however, it increased by 26% for an increase in strain rate from 0.1 to 1500 s⁻¹ for the uniaxial condition. Initial triaxiality was found to have a significant negative impact on true failure strain with a decrease of 32% at the highest triaxiality compared to the uniaxial condition at a strain rate of 0.001 s⁻¹. High resolution scanning electron microscopy images of the failure surfaces revealed a dimpled surface while optical micrographs revealed shearing through the thickness indicating failure occurred via ductile-shear. Finite element simulations of the tests were used to predict the effective plastic strain versus triaxiality history within the deforming specimens. These predictions were combined with the measured conditions at the onset of failure in order to construct limit strain versus triaxiality failure criteria.     

The effect of target strength on the perforation of steel plates using three different projectile nose shapes

The effect of target strength on the perforation of steel plates is studied. Three structural steels are considered: Weldox 460 E, Weldox 700 E and Weldox 900 E. The effects of strain hardening, strain rate hardening, temperature softening and stress triaxiality on material strength and ductility are determined for these steel alloys by conducting three types of tensile tests: quasi-static tests with smooth and notched specimens, quasi-static tests at elevated temperatures and dynamic tests over a wide range of strain rates. The test data are used to determine material constants for the three different steels in a slightly modified version of the Johnson–Cook constitutive equation and fracture criterion.Using these three steel alloys, perforation tests are carried out on 12 mm-thick plates with blunt-, conical- and ogival-nosed projectiles. A compressed gas gun was used to launch projectiles within the velocity range from 150 to 350 m/s. The initial and residual velocities of the projectile were measured, while the perforation process was captured using a digital high-speed camera system. Based on the test data the ballistic limit velocity was obtained for the three steels for the different nose shapes. The experimental results indicate that for perforation with blunt projectiles the ballistic limit velocity decreases for increasing strength, while the opposite trend is found in tests with conical and ogival projectiles. The tests on Weldox 700 E and Weldox 900 E targets with conical-nosed projectiles resulted in shattering of the projectile nose tip during penetration.Finally, numerical simulations of some of the experimental tests are carried out using the non-linear finite element code LS-DYNA. It is found that the numerical code is able to describe the physical mechanisms in the perforation events with good accuracy. However, the experimental trend of a decrease in ballistic limit with an increase in target strength for blunt projectiles is not obtained with the numerical models used in this study.     

Constitutive modeling for flow stress of 55SiMnMo bainite steel at hot working conditions

The hot deformation behavior of 55SiMnMo bainite steel was studied through isothermal hot compression tests conducted using a Gleeble 3500 at 950–1100 °C, with strain rates of 0.01 s⁻¹ to 10 s⁻¹. A constitutive equation was established using the experimental results to describe the stress–strain relationship based on the dislocation density variation, considering the influence of the dynamic softening mechanism. When dynamic recovery is the only softening mechanism, a constitutive equation for flow stress was obtained from the variation of the dislocation density during hot deformation based on work hardening and dynamic recovery. When dynamic recrystallization occurs, the relationship between the dislocation density and the volume fraction of dynamic recrystallization was used to predict the flow stress after the peak. The reliability of the model was verified through a comparison between the predicted flow stress curves from the model and the experimental data.     

Thermomechanical response of HSLA-65 steel plates: experiments and modeling

To understand and model the thermomechanical response of high-strength low-alloy steel (HSLA-65), uniaxial compression tests are performed on cylindrical samples, using an Instron servohydraulic testing machine and UCSD’s enhanced Hopkinson technique. True strains exceeding 60% are achieved in these tests, over the range of strain rates from 10⁻³/s to about 8500/s, and at initial temperatures from 77 to 1000 K. The microstructure of the undeformed and deformed samples is examined through optical microscopy.The experimental results show: (1) HSLA-65 steel displays good ductility and plasticity (strain > 60%) even at low temperatures (even at 77 K) and high strain rates; (2) at relatively high temperatures and low strain rates (especially below about 0.1/s), its strength is temperature-insensitive, indicating that the material has good high-temperature weldability; (3) slight dynamic strain aging (DSA) occurs at temperatures over 400 K and in the range of strain rates from 0.001/s to 3000/s, the maximum values of the stress shifting to higher temperatures with increasing strain rates; and (4) the microstructure of the material is not affected much by the changes in the strain rate and temperature.Finally, based on the mechanism of dislocation motion, and using our experimental data, the parameters of a physically-based model developed earlier for AL-6XN stainless steel [J. Mech. Phys. Solids 49 (2001) 1823] are estimated and the model predictions are compared with various experimental results, excluding the dynamic strain aging effects. Good agreement between the theoretical predictions and experimental results is obtained. In order to further verify the model independently of the experiments used for the evaluation of the model parameters, additional compression tests at a strain rate of 8500/s and various initial temperatures are performed, and the results are compared with the model predictions. Good correlation is observed. As an alternative to this model, the experimental data are also used to estimate the parameters in the Johnson–Cook model [Proceedings of the Seventh International Symposium on Ballistics, The Hague, The Netherlands, p. 541] and the resulting model predictions are compared with the experimental data, again excluding the dynamic strain-aging effects. These and related results suggest that the physically-based model has a better prediction capability over a broader strain rate and temperature range.