摘要
采用物理模拟实验和理论计算研究了新一代反应堆压力容器用SA508Gr.4N钢的奥氏体化转变与晶粒长大动力学。结果表明:实验钢的奥氏体化临界温度A_(c1)和A_(c3)分别为714℃和773℃;转变速率随过热度的增大先增加后减小,具有S型动力学特性;得到了适用于SA508Gr.4N钢的奥氏体化临界温度A_(c1)和A_(c3)的预测模型。理论计算结果表明:当Ni含量超过3.5%时,在500℃及以下存在奥氏体稳定相;Cr大幅降低了钢中C的活度,抑制Fe_(3)C渗碳体的形成,SA508Gr.4N钢中碳化物主要是M_(23) C_(6)型合金碳化物;奥氏体晶粒尺寸随加热温度的升高、保温时间的延长而增大,非线性拟合得到了奥氏体晶粒长大动力学模型。
Austenitizing transformation and grain growth kinetics of SA508Gr.4N steel for new generation reactor pressure vessels were studied by physical simulation experiment and theoretical calculation.The results show that the austenitizing critical temperatures A_(c1) and A_(c3) of the experimental steel are 714℃and 773℃,respectively.The transformation rate increases first and then decreases with the increase of superheat,which has sigmoid dynamic characteristics.The prediction models for austenitizing critical temperatures A_(c1) and A_(c3) of the SA508Gr.4N steel are derived.The theoretical calculation results show that when the Ni content exceeds 3.5%,there is austenite stable phase at 500℃and below.Cr greatly reduces the activity of C in the SA508Gr.4N steel and inhibits the formation of Fe_(3)C cementite,and the carbides in the SA508Gr.4N steel are mainly M_(23) C_(6) alloy carbides.The austenite grain size increases with the increase of heating temperature and holding time.The dynamic model of austenite grain growth is obtained by nonlinear fitting.
作者
万莉
陆书萌
郑善举
李萌蘖
熊茹
WAN Li;LU Shu-meng;ZHENG Shan-ju;LI Meng-nie;XIONG Ru(Faculty of Materials Science and Engineering,Kunming University of Science and Technology,Kunming 650093,China;State Key Laboratory for Nuclear Fuel and Materials,Nuclear Power Institute of China,Chengdu 610213,China)
出处
《材料热处理学报》
CAS
CSCD
北大核心
2022年第5期186-194,共9页
Transactions of Materials and Heat Treatment
基金
反应堆燃料及材料重点实验室开放基金(STRFML-2020-03)
云南省基础研究计划项目(202101AU070152)。
