DD3单晶超合金蠕变性能及γ'变形组织观察

Creep Property and γ＇Deformed Microstructure of Single Crystal DD3

研究了DD3单晶合金在不同气氛中的高温蠕变断裂性能和蠕变过程中γ＇粒子的变形特征。结果表明，气氛对合金的蠕变性能影响很大，在热腐蚀环境中，DD3合金可能发生早期失效，但涂层能有效地改善合金在热腐蚀环境中的高温蠕变性能。蠕变过程中，形成γ＇粒子的筏排结构，超位错切割γ＇粒子的位错攀移是蠕变变形的主要机制。

篢he creep-rupture property and γ＇deformed structure characteristic of DD3 alloy, a kind of Ni base single crystal superalloy, were investigated in different environment.Environment had great effects on the creep properties of DD3 alloy at elevated temperature. In hot corrosion environment DD3 alloy would fracture prematurely and disastrously, however, Pt-Al coating could efficiently improve the high temperature creep performances. The γ＇rafts and subgrain boundaries with dislocation configuration were formed during creep deformation. Superlattice dislocation cutting through and climbing over γ＇particles were the two predominant deformation rnechanisms