【作者】 王洋； 张政睿； 陈超； 刘涛； 闫琦吉； 林万明；

【Author】 WANG Yang;ZHANG Zhengrui;CHEN Chao;LIU Tao;YAN Qiji;LIN Wanming;College of Materials Science and Engineering, Taiyuan University of Technology;College of New Energy and Materials Engineering, Shanxi Electronic Science and Technology Institute;

【机构】 太原理工大学材料科学与工程学院； 山西电子科技学院新能源与材料工程学院；

【摘要】 316L奥氏体不锈钢磁性来源为残留铁素体相。本文对AISI316L奥氏体不锈钢连铸方坯的残留铁素体特征进行了研究。通过低倍组织观察发现,铸坯可划分为表层细晶区、柱状晶区和中心等轴晶区三个区域,各区域的厚度和晶粒结构有所差异,其中表面细晶区厚度为20mm,柱状晶区厚度为50mm,等轴晶区厚度为40mm。在细晶区,残留铁素体呈颗粒状和板条状分布于奥氏体晶界处。柱状晶区的残留铁素体主要以骨骼状存在,并向内逐渐变为不连续的网状结构。铁素体含量表面细晶区最少,中心等轴晶区最多。铁素体中Cr元素富集、Ni元素贫乏,奥氏体中Ni元素富集、Cr元素贫乏,且不同区域铁素体和奥氏体化学成分有区别。更多还原

【Abstract】 The magnetic source of 316L austenitic stainless steel is the residual ferrite phase. In this paper, the residual ferrite characteristics of AISI316L austenitic stainless steel continuous casting billet were studied. Through metallographic observation, it is found that the casting billet can be divided into three regions: surface fine crystal region, columnar crystal region and central equiaxed crystal region. The thickness and grain structure of each region are different. The thickness of surface fine crystal region is 20mm, the thickness of columnar crystal region is 50mm, and the thickness of equiaxed crystal region is 40mm. In the fine grained region, the residual ferrite is distributed in granular and lathy form at the boundaries of austenite. The residual ferrite in the columnar crystal area mainly exists in skeletal form, and gradually changes inward into discontinuous network structure. The content of ferrite is the least in the surface fine crystal region and the most in the central equiaxed crystal region. The ferrite is rich in Cr and poor in Ni, and the austenite is rich in Ni and poor in Cr, and the chemical composition of ferrite and austenite is different in different regions.更多还原