Author(s)

Rafael P. Ferreira¹, Eden S. Silva^1,2, Carmem C. F. Nascimento¹, Samuel F. Rodrigues^1,3*, Clodualdo Aranas Jr.³, Valdemar S. Leal¹, Gedeon S. Reis¹

¹Graduate Program in Materials Engineering, Federal Institute of Education, Science and Technology of Maranhão—IFMA, São Luís, MA, Brazil.
²Engineering Coordination, Universidade UNICEUMA, São Luís, MA, Brazil.
³Department of Materials Engineering, McGill University, Montreal, Canada.

The analytical approach and the thermomechanical behavior of a Cr-Ni-Mo-Mn-N austenitic stainless steel were characterized based on the parameters of work hardening (h), dynamic recovery (r) and dynamic recrystallization (n, t_0.5), considering constitutive equations (σ, ε) and deformation conditions expressed according to the Zener-Hollomon parameter (Z). The results indicated that the curves were affected by the deformation conditions and that the stress levels increased with Z under high work hardening rates. The σ_c/σ_p ratio was relatively high in the first part of the curves, indicating that softening was promoted by intense dynamic recovery (DRV). This was corroborated by the high values of r and average stacking fault energy, γ_sfe = 66.86 mJ/m², which facilitated the thermally activated mechanisms, increasing the effectiveness of DRV and delaying the onset of dynamic recrystallization (DRX). The second part of the curves indicates that there was a delay in the kinetics of dynamic softening, with a higher value of t_0.5 and lower values of the Avrami exponent (n) due to the competing DRV-DRX mechanisms, and steady state stress (σ_ss) was achieved under higher rates of deformation.

Austenitic Stainless Steel, Dynamic Recovery, Dynamic Recrystallization

Ferreira, R. , Silva, E. , Nascimento, C. , Rodrigues, S. , Aranas Jr., C. , Leal, V. and Reis, G. (2016) Thermomechanical Behavior Modeling of a Cr-Ni-Mo-Mn-N Austenitic Stainless Steel. Materials Sciences and Applications, 7, 803-822. doi: 10.4236/msa.2016.712062.