06Ni9钢回转奥氏体的形成及稳定性研究  

Investigation on Formation Process and Stability of Reverted Austenite in 06Ni9 Steel

作　　者：周瑰云 刘东风[1,2] 卫英慧[2] 杨秀丽[2] 侯利锋[2] 

机构地区：[1]太原钢铁(集团)有限公司技术中心,太原030005 [2]太原理工大学材料科学与工程学院,太原030024

出　　处：《太原理工大学学报》2010年第3期220-223,共4页Journal of Taiyuan University of Technology

基　　金：国家863计划资助项目(2007AA03Z555)

摘　　要：针对06Ni9钢回火时回转奥氏体的形成过程存在模糊认识问题,在Fe-Ni相图的基础上,较深入地分析了回转奥氏体的形成过程,包括碳原子的析出、奥氏体的形成和合金元素的再分配,同时讨论了回转奥氏体的稳定性。研究表明,06Ni9钢淬火后回火时,回转奥氏体回火温度太高,奥氏体数量增多,减小了其合金化程度;回火温度太低,原子扩散能力减弱,可能形成脆性的金属间化合物,所以存在最佳的回火温度范围（540-620℃）。为了保证06Ni9钢较高的低温冲击韧度,回转奥氏体数量（质量分数）应控制在10%以下。06Ni9 is a structural steel used in making storage tanks of liquified natural gas （LNG）. In the paper, formation process of reverted austenite, including precipitation of carbon atom, formation of austenite and redistribution of alloying elements, was analyzed in more detail on the basis of Fe-Ni phase equilibrium diagram in order to clarify the phase transformation process during tempering. And stability of the reverted austenite was also dealt with at the same time. It is concluded that the formation process of the reverted austenite is of special characteristics. There is an optimum temperature range for the 06Ni9 steel. If the tempering temperature is higher than the range, the reverted austenite would increase, which leads to decrease in alloying elements in the reverted austenite. On the contrary, at a lower tempering temperature diffusion ability of the solute atoms would slow down and ordered intermetallic compound L12, a brittle phase, would possibly form. In order to enhence the cryogenic impact toughness of the 06Ni9 steel, the reverted austenite should be controlled less than 10 %.

关 键 词：06NI9钢 回转奥氏体形成 低温冲击韧度 

分 类 号：TG156.5[金属学及工艺—热处理]