中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 33 No. 8 August 2023 |
（1. Fujian Provincial Key Laboratory of Materials Genome, College of Materials, Xiamen University, Xiamen 361005, China;
2. Xiamen Key Laboratory of High Performance Metals and Materials, Xiamen University, Xiamen 361005, China;
3. Institute of Materials Genome and Big Data, Harbin Institute of Technology, Shenzhen 518055, China）
Abstract:Considering the (210)[001] grain boundary of Co as a model, the influence of transition metals and their coupling with O on the grain boundary energy and strength was investigated by a first-principles-based study. Quantitative characterization was used to explain the transition metal segregation at the grain boundary, and the negative correlation between grain boundary energy and atomic radius was revealed. It has been found that the interaction between the solute and the host atoms at the grain boundary affects the grain boundary strength. Re, W, Os, Cr, Tc, Mo, Ir, Ta, Zr, Ru, Nb, V, Rh, Pt, Pd, and Ni can significantly strengthen the grain boundary, while other transition metals have a weakening effect on the grain boundary. In particular, Cr, Hf, Ta, W, Re, Os, Ir, and Pt can effectively alleviate the weakening of the grain boundary caused by O atoms.
Key words: transition metal elements; oxygen; Co-based superalloys; first-principles calculation; segregation; grain boundary energy; grain boundary strength
