316L不锈钢梯度结构及其在退火中的演变  

Surface Gradient Structure of 316L Stainless Steel Treated by SMA and its Evolution During Annealing

作　　者：王爱香[1,2] 刘刚[1] 周蕾[1] 吕爱强[1] 杨晓华[3] 李瑛[4] 

机构地区：[1]中国科学院金属研究所沈阳材料科学国家(联合)实验室 [2]福州大学材料科学与工程学院,福建福州350002 [3]福州大学材料科学与工程学院 [4]中国科学院金属研究所金属腐蚀与防护国家重点实验室

出　　处：《材料热处理学报》2005年第4期12-16,共5页Transactions of Materials and Heat Treatment

基　　金：国家自然科学基金项目(50071061);中国科学院知识创新工程重要方向项目;国家"863"计划项目资助

摘　　要：对316L不锈钢进行表面机械研磨处理(SMAT),获得表面为纳米晶、晶粒尺寸沿厚度方向逐渐增大的梯度组织。对SMAT样品进行不同温度的真空退火,研究组织变化。结果表明:当退火温度低于0.5Tm(Tm为熔点)时,316L不锈钢经SMAT后形成的梯度组织未发生明显的变化。随着退火温度的继续增加,梯度组织发生回复和晶粒长大,但晶粒长大的速度较小。整个退火过程中,内应力和微观应变的释放在SMAT样品的深度方向诱发了机械孪生,并在纳米结构表层中引起马氏体相变。316L stainless steel plate was treated by means of surface mechanical attrition treatment (SMAT) technique, and a gradient structure consisting of gradually increased grain size from nano-scale in the surface layer to micro-scale in the matrix was obtained. The SMAT sample was annealed in vacuum at different temperatures, and the structural evolution was analyzed. The results show that no obvious change can be found for the gradient structure when the annealing temperature is lower than 0.5 Tm (Tm is melt point of the steel). With increasing annealing temperature, recovery and grain growth occur in the gradient structure, however the grain growth rate is very low. The release of internal stress and micro-strain induce mechanical twinning below surface layer and martensite transformation in the nanostructured surface layer during annealing.

关 键 词：316L不锈钢 表面纳米化 退火 组织 

分 类 号：TG111.7[金属学及工艺—物理冶金]