中合金重锻件钢中共晶碳化物的溶解行为

Dissolution Behavior of Eutectic Carbides in Medium-Alloy Steels for Heavy Forgings.

作者信息

Ji Yu, Xu Tingting, Zhao Caiyan, Chen Guangyao, Zhao Hongshan, Hu Chundong, Dong Han

机构信息

School of Materials Science and Engineering, Shanghai University, Shanghai 200444, China.

Zhongyuan Special Steel Co., Ltd., Jiyuan 459000, China.

出版信息

Materials (Basel). 2023 Oct 19;16(20):6763. doi: 10.3390/ma16206763.

DOI:10.3390/ma16206763

PMID:37895745

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC10608740/

Abstract

In this study, we investigate the dissolution behavior of eutectic carbides in heavy forgings. High-temperature diffusion treatment was conducted on 35Cr3Ni3MoVW2 (MoVW2) and 35Cr2Ni3MoV (MoV) steels at 1230 °C for a duration ranging from 0 to 100 h. The dissolution of eutectic carbides and its effects on the microstructure and hardness of the steels were characterized and analyzed via SEM+EBSD, ImageJ, and Thermo-Calc. The results show that the coarse eutectic carbides in both steels gradually dissolved. The distribution and morphology tend to be uniform and spherical, respectively. For holding 50 h, the hardness of both steels significantly exhibited an increasing trend, and it was attributed to the combined effects of solid solution strengthening. Thermodynamic calculations indicated that the higher W content in MoVW2 steel promoted the precipitation of MC eutectic carbides. Moreover, both MoVW2 and MoV steels exhibited the precipitation of MC eutectic carbides in the final stage of solidification, facilitated by the enrichment of C and Cr in the liquid steels.

摘要

在本研究中，我们研究了重型锻件中共晶碳化物的溶解行为。对35Cr3Ni3MoVW2（MoVW2）钢和35Cr2Ni3MoV（MoV）钢在1230℃下进行了0至100小时的高温扩散处理。通过扫描电子显微镜+电子背散射衍射（SEM+EBSD）、ImageJ软件和Thermo-Calc软件对共晶碳化物的溶解及其对钢的微观结构和硬度的影响进行了表征和分析。结果表明，两种钢中的粗大共晶碳化物逐渐溶解。其分布和形态分别趋于均匀和球形。保温50小时时，两种钢的硬度均显著呈现上升趋势，这归因于固溶强化的综合作用。热力学计算表明，MoVW2钢中较高的W含量促进了MC共晶碳化物的析出。此外，MoVW2钢和MoV钢在凝固末期均出现了MC共晶碳化物的析出，这是由于液态钢中C和Cr的富集所致。