文献类型：期刊文献

英文题名：Effect of yttrium introduction on the microstructure and properties of 440C stainless steel prepared by spark plasma sintering

作者：Nie, Xiaowu[1];Jiang, Qiaoding[1];Liang, Liwei[1];Huang, Xunuo[1]

机构：[1]Guangdong Ocean Univ, Sch Mat Sci & Engn, Yangjiang 529500, Peoples R China

年份：2027

卷号：427

外文期刊名：MATERIALS LETTERS

收录：SCI-EXPANDED(收录号：WOS:001901182700001)、、WOS

基金：This work is funded by the Doctoral Startup Scientific Research Project of Guangdong Ocean University (YJR22017), the Special Project for the Revitalization of Key Industrial Talents in Alloy Materials and Hardware Knife and Scissors in Yangjiang City (RCZX2024018), and the Student Innovation Team Project of Guangdong Ocean University (CXTD2025011) and College Student Innovation and Entrepreneurship Training Program Project (S202610566057).

语种：英文

外文关键词：440C stainless steel; Spark plasma sintering; Yttrium; Microstructure; Mechanical properties

外文摘要：This study employs spark plasma sintering (SPS) to prepare 440C martensitic stainless steel with varying yttrium (Y) additions, investigating the effects of Y on microstructure and mechanical properties. All samples achieve relative densities above 98.5%. With increasing Y content, hardness and compressive strength first increase and then decrease, peaking at 1.2 wt% Y. The 1.2 wt% Y alloy exhibits an average grain size of 0.78 mu m and a compressive strength of similar to 2000 MPa, which is similar to 35% higher than the Y-free control (1480 MPa). Excessive Y (1.4 wt%) forms coarse Y2O3 inclusions at grain boundaries, deteriorating mechanical properties. The strengthening mechanisms include fine-grain strengthening, solid-solution strengthening, and dispersion strengthening of fine carbides. This study provides a theoretical basis for rare-earth microalloying design of high-performance powder metallurgy stainless steels.