Dynamic Recrystallization Behavior of a Heat-resistant Martensitic Stainless Steel 403Nb during Hot Deformation

• Published in: Journal of materials science & technology Vol. 27; no. 10; pp. 913 - 919
• Main Authors: Zeng, Zhouyu, Chen, Liqing, Zhu, Fuxian, Liu, Xianghua
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.10.2011
• Subjects: 403Nb steel; Constitutive relationships; Critical strain; Deformation; Dynamic recrystallization; Hot deformation; Martensitic stainless steels; Mathematical models; Strain; Strain rate; Stresses; 再结晶行为; 动力学方程; 动态再结晶; 变形过程; 应变率; 真实应力; 耐热不锈钢; 马氏体不锈钢; Hot deformation; 403Nb steel; Dynamic recrystallization; Critical strain
• ISSN: 1005-0302; 1941-1162
• DOI: 10.1016/S1005-0302(11)60164-3

Dynamic recrystallization （DRX） behaviors of a heat-resistant martensitic stainless steel 403Nb during hot deformation have been investigated by single-pass thermo-mechanical simulative experiment at temperatures of 900-1150℃ and strain rates of 0.01-1 s-1 The results show that the true stress-true strain curves of this alloy can be classified into two types, one is of dynamic recovery and the other is of dynamic recrystallization. The DRX in 403Nb alloy is easy to occur at strain rates lower than 0.5 s-1 and deformation temperatures higher than 1000℃. Using regression analysis, the stress multiplier （a） and apparent stress exponent （n） were calculated to be 0.0153 and 3.22, respectively, while the activation energy （Qd） for DRX of 403Nb was calculated to be 367.293 kJ/mol. The constitutive equation of peak stress for DRX was also obtained. Based on P-J method, the critical strain for DRX was accurately determined. The mathematical models of peak strain and kinetic equation for DRX of 403Nb steel were finally established.