【作者】 肖俊； 张月； 崔译夫； 郄镕鉴； 赵爱民；

【Author】 Xiao Jun;Zhang Yue;Cui Yifu;Qie Rongjian;Zhao Aimin;University of Science and Technology Beijing;

【机构】 北京科技大学钢铁共性技术协同创新中心；

【摘要】 采用热力学计算与实验相结合,借助高温共聚焦显微镜、EBSD、光学显微镜和场发射扫描电镜重点探讨钢中添加稀土钇对超级奥氏体不锈钢凝固组织以及固态相变的影响,并对第二相σ析出进行了表征。结果表明,钢中主要析出相为σ相,在凝固过程中,Cr和Mo元素偏析越来越严重,形成了σ相周围存在Cr和Mo元素贫化区。添加稀土Y能提高超级奥氏体不锈钢的等轴晶率,降低铸件边缘和R/2处共析组织体积分数。通过对654SMO凝固过程的原位观察,表明稀土Y可以提高形核温度,减小凝固温度范围,均匀并细化凝固组织,并发现了共析组织的原位析出过程。更多还原

【Abstract】 Combining thermodynamic calculations with experiments, with the help of high-temperature confocal microscope, EBSD, optical microscope and field emission scanning electron microscope, the effect of adding rare earth yttrium in steel on the solidification structure and solid phase transformation of super austenitic stainless steel is focused on,and the effect of the second phase The σ precipitation was characterized. The results show that the main precipitated phase in the steel is the σ phase. During the solidification process, the segregation of Cr and Mo elements becomes more and more serious, revealing the existence of Cr and Mo element depleted areas around the σ phase. The addition of rare earth Y can increase the equiaxed crystal ratio of super austenitic stainless steel and reduce the volume fraction of eutectoid structure at the edge of the casting and at R/2. Through in-situ observation of the solidification process of 654SMO, it is shown that rare earth Y can increase the nucleation temperature, reduce the solidification temperature range, uniform and refine the solidification structure, and found the in-situ precipitation process of the eutectoid structure.更多还原