Hot Deformation Behavior of SA508GR. 4N Steel for Nuclear Reactor Pressure Vessels

• Published in: Journal of iron and steel research, international Vol. 23; no. 12; pp. 1342 - 1348
• Main Authors: LIU, Ning, LIU, Zheng-dong, HE, Xi-kou, YANG, Zhi-qiang, MA, Long-teng
• Format: Journal Article
• Language: English
• Published: Singapore Elsevier Ltd 01.12.2016; Springer Singapore
• Subjects: Applied and Technical Physics; dynamic recrystallization; Engineering; hot deformation equation; hot processing map; Machines; Manufacturing; Material; Materials Engineering; Materials Science; Metallic Materials; Physical Chemistry; Processes; SA508GR.4N steel; Zener-Hollomon parameter; 低合金钢; 动态再结晶; 双曲正弦函数; 核反应堆压力容器; 热变形激活能; 热变形行为; 真应力-应变曲线; 试验温度; SA508GR.4N steel; dynamic recrystallization; hot processing map; Zener-Hollomon parameter; hot deformation equation; SA508GR. 4N steel
• ISSN: 1006-706X; 2210-3988
• DOI: 10.1016/S1006-706X(16)30197-2

A hot compression experiment （1073 1473 K, strain rates of 0. 001-10 s -1 ） of SAS08GR. 4N low alloy steel was performed using a Gleeble-3800 thermal-mechanical simulator, and the hot deformation behavior of the steel was investigated by analyzing both the true stress true strain curves and its microstructures. The thermal de formation equation and hot deformation activation energy （Q） of SA508GR. 4N steel were obtained by regression with a classic hyperbolic sine function. The hot processing map of SAS08GR. 4N steel was also established. An empirical equation for the stress peak was described for practical applications. The SA508GR. 4N steel showed a critical Zener-Hollomon parameter （lnZc） for dynamic recrystallization （DRX） of 37.44, below which full DRX may occur. The sensitivity of the SA508GR. 4N steel increased linearly with test temperature, such that higher temperatures led to enhanced workability.