Effect of annealing temperature on mechanical properties of ECAP high-nitrogen austenitic stainless steel

doi:10.13251/j.issn.0254-6051.2021.11.013

Abstract

Abstract: In order to study the effect of equal channel angular pressing (ECAP)+ annealing process on mechanical behavior of the high-nitrogen steel, single pass ECAP deformation was performed on high-nitrogen steel at room temperature, and then the steel with different N contents was annealed at 700, 800, 850, 900 ℃, respectively, to analyze the change rules of mechanical properties. The results show that the yield strength and tensile strength of the high-nitrogen steel decrease on the whole with the increase of annealing temperature, while the plasticity increases. The tensile strength and uniform elongation of the high-nitrogen steel at different annealing temperatures show the traditional inverse relationship, and the strength and uniform elongation increase synchronously with the increase of N content. The tensile fracture morphology of high nitrogen steel ECAP + annealed at low temperatures is intergranular, and intergranular fracture tendency is more obvious with the increase of N content.

Key words: high-nitrogen austenitic stainless steel, equal channel angular pressing (ECAP), annealing temperature, mechanical properties

CLC Number:

Hou Junfeng, Xu Wang, Zhang Mingxu, Li Yongze, Dong Fuyuan. Effect of annealing temperature on mechanical properties of ECAP high-nitrogen austenitic stainless steel[J]. Heat Treatment of Metals, 2021, 46(11): 84-89.

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