Work

Weighted average study of transition metal segregation at Ni grain boundaries and its effect on grain boundary cohesion

Year: 2025

Type: article

Abstract: High-performance Ni-based alloys often exhibit reduced grain boundary (GB) cohesion under high-stress or elevated-temperature conditions, necessitating further enhancement. This study investigates the segregation of 18 transition elements at Ni GBs using a weighted average method combined with first-principles calculations. The results reveal that the segregation behavior of transition metal at GBs in nickel-based alloys is influenced by the GB type, temperature and initial bulk concentration. An obvious linear correlation is observed between atom probe tomography (APT) measured and density functional theory (DFT) predicted GB concentrations in nickel-based alloy 725. Notably, the GB segregations of Mn, V, Co, Nb, Ti, Mo, Fe, and Cr are found to enhance GB cohesion. The site- and GB-weighted average method provides a novel framework for cross-validating DFT simulations with experimental data.

Source: Journal of Materials Research and Technology

DOI: 10.1016/j.jmrt.2025.03.099

Authors: Yanyan Shi, Hongtao Xue, Fuling Tang, Ruidong Dang, Fengjuan Si, Yuxia Hu

Institutions: Lanzhou University of Technology, Lanzhou City University

Language: English

Topic: Microstructure and mechanical properties

Subfield: Materials Chemistry

Field: Materials Science

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $1,640

Funders: National Natural Science Foundation of China, Major Science and Technology Project of Hainan Province