Thermo-viscoplastic behavior of 304 austenitic stainless steel at various strain rates and temperatures: Testing, modeling and validation

Abstract

This paper presents a systematic study of the thermo-viscoplastic behavior of a 304 austenitic stainless steel (ASS). The experiments were conducted over a wide range of strain rates (10 − 3 s − 1 to 3270 s − 1) and temperatures (-163°C to 172°C), for which the deformation behavior of 304 ASS becomes more complex due to the straininduced martensitic transformation (SIMT) effect. Dynamic tests at low/elevated temperatures were conducted using the Hopkinson technique coupled with a cooling device/heating furnace, and temperature distribution within the specimen was verified to be uniform. Experimental results showed that the strain hardening rate of 304 ASS was strongly affected by SIMT effect. For quasi-static tests (10 − 3 s − 1 to 1 s − 1) at low temperatures (-163°C to-20°C), the stress-strain relations exhibited an S-shape and a second strain hardening phenomenon. The strain rate sensitivity and temperature sensitivity of 304 ASS were also different from metallic materials deformed by dislocation glide. Several unexpected phenomena including the negative strain rate sensitivity and the changing temperature sensitivity from quasi-static to dynamic tests were observed. Based on experimental results, an extension of the Rusinek-Klepaczko (RK) model considering SIMT effect was used to simulate the deformation behavior of 304 ASS: it predicted flow stress curves of 304 ASS above-60°C correctly. In addition, to validate the extended RK model and the identified model parameters, numerical simulations of ballistic impact tests of 304 ASS plates at various temperatures were carried out, showing a good agreement with experiments.

Simple shear behavior and constitutive modeling of 304 stainless steel over a wide range of strain rates and temperatures

“…This is because with increasing strain rate, martensitic transformation is gradually reduced by adiabatic heating, and the corresponding strength decreases [9][10][11]. A similar fact was observed by Jia et al during uniaxial compression tests at strain rates between 10 − 3 and 3270 s − 1 [12].…”

Understanding novel gap-bridged remote laser welded (RLW) joints for automotive high-rate and temperature applications

“…Therefore, the ductility and peak strength of the RLW samples were increased with the test speed from 0.1 m/s to 1.0 m/s. In general, the main difference in mechanical behaviours from static to dynamic testing can be attributed to the activation of different slip systems, differences in dislocation mobility, pile up and accommodation processes under different strain rates [58,59]. Furthermore, the increased ductility of the RLW joint sample can be attributed to the inertia effects of the whole sample geometry.…”

Aquisição numérica do perfil tensão deformação durante passagem de fonte de calor nos materiais AISI 410, 304L e 430

“…Os gráficos da Figura 2 mostram os pontos de medição de tensão, no início do deslocamento da fonte de calor, a de distância. (Jia, 2020). Visto isso, o interesse das propriedades dos materiais inoxidáveis pela indústria, deve ser intrínseco as suas propriedades finais caso esse material trabalhe em ambientes com variação térmica.…”

“…A velocidade com o qual a tensão aumenta ao longo da geometria de cada material, é um fator de alta relevância para a transformação estrutural e microestrutural (Jia, 2020 (Bauchau & Craig, 2009;Norton, 2013). Research, Society and Development, v. 9, n. 7, e286974224, 2020 (CC BY 4. Na Figura 4, temos a deformação total de cada material estudado, para a malha 1, após o deslocamento da fonte de calor.…”