Stabilizing nanograined Fe-Cr alloy by Si-assisted grain boundary segregation

作     者：X.F.Xu X.Y.Li B.Zhang X.F.Xu;X.Y.Li;B.Zhang

作者机构：Shenyang National Laboratory for Materials ScienceInstitute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026China 

出 版 物：《Journal of Materials Science & Technology》 (材料科学技术（英文版）)

年 卷 期：2023年第134卷第3期

页      面：223-233页

核心收录：

学科分类：07[理学] 08[工学] 070205[理学-凝聚态物理] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学] 0703[理学-化学] 0702[理学-物理学] 

基　　金：supported by the Ministry of Science and Technology of the People’s Republic of China(Nos.2017YFA0204401 2017YFA0700700). 

主　　题：Segregation Grain boundary Fe-Cr-Si alloy Nanocrystalline Thermal stability 

摘      要：Intentional solute segregation at grain boundary(GB)can effectively stabilize the nanograined alloys by reducing the excess energy and mobility of GB,but it usually works for binary alloys with sufficient GB segregation tendency.Here,we found that the segregation of Cr can be enhanced in a nanostruc-tured Fe-8Cr alloy with insufficient GB segregation tendency through the interaction of another solute Si(1.0 wt.%).After surface mechanical grinding treatment and subsequent annealing,the nanograined Fe-8Cr-1Si is more thermally stable than the nanograined Fe-8Cr,which is mainly attributed to the Si-enhanced Cr segregation as observed by Super-X energy-dispersive X-ray spectroscopy(EDS)mapping system.With the grain refinement to nanoscale,the thermal stability is further improved due to the in-crease of Cr content at GBs and the precipitates formed at appropriate high temperatures.The present finding provides guidance for the development of advanced nanostructured ternary alloys.