The effect of substituting Mo for W on γ/γ′ partitioning behaviors of alloying elements in heat-treated second generation Ni based single crystal superalloys was investigated via atom probe tomography technique. Re, Cr, Co and Mo elements tended to distribute in γ phase, while Al, Ta and W elements tended to distribute in γ′ phase, and significant interfacial segregation was not found in experimental alloys. Moreover, substituting Mo for W obviously increased Re content in γ phase. Meanwhile, Re content in γ phase increased with increasing Mo + Cr content in single crystal superalloy, while Re content in γ′ phase decreased with increasing W + Ta content in single crystal superalloy. In addition, partitioning ratios of both W and Mo elements were positively correlated with Ta content in single crystal superalloy, and partitioning ratio of Ta element was inversely correlated with Ta/Al ratio in single crystal superalloy. Furthermore, substituting Mo for W increased the solid solution strength of γ phase but decreased the solid solution strength of γ′ phase.

通过原子探针层析成像技术研究了用钼代替钨对热处理后的第二代镍基单晶高温合金中合金元素的γ/γ′分配行为的影响。Re，Cr，Co和Mo元素倾向于在γ相中分布，而Al，Ta和W元素倾向于在γ′相中分布，并且在实验合金中未发现明显的界面偏析。此外，用Mo代替W会明显增加γ相中的Re含量。同时，随着单晶高温合金中Mo + Cr含量的增加，γ相中的Re含量增加；随着单晶高温合金中W + Ta含量的增加，γ'相中的Re含量降低。此外，单晶高温合金中W和Mo元素的分配比与Ta含量呈正相关，在单晶高温合金中，Ta元素的分配比与Ta / Al比成反比。此外，用Mo代替W增加了γ相的固溶强度，但是降低了γ′相的固溶强度。