中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 30 No. 10 October 2020 |
（1. School of Metallurgy, Northeastern University, Shenyang 110819, China;
2. Beijing Institute of Aeronautical Materials, Aero Engine Corporation of China, Beijing 100095, China）
Abstract:The fundamental mechanism of the cracking formation was investigated for the as-cast GH4151 superalloy. By analyzing the characteristics of cracking, the cracking mechanism was determined to be the cold crack formed during the cooling process. And cold cracking is closely related to severe segregation, complex precipitates and uneven γ'''' phase distribution. During cooling process, cracks were generated around the precipitates due to their different linear shrinkage coefficients. The annealing treatment process controlling the residual stress, the size and morphology of γ'''' phase was proposed. The annealing treatment plays a role in reducing residual stress through decreasing the thermal gradient and controlling the size distribution of γ'''' phase to reduce the strain concentration around the precipitate phases.
Key words: GH4151 alloy; as-cast ingot; cracking mechanism; residual stress; γ'' phase
