喷射沉积Ni_3Al-Mo合金的位错结构分析

Dislocation structure of spray deposited Ni_3Al Mo alloy

利用多功能雾化沉积装置制备了Ｎｉ－Ａｌ－Ｍｏ 系Ｎｉ３Ａｌ基高温合金。拉伸性能测试表明，喷射沉积Ｎｉ３Ａｌ－Ｍｏ 合金的屈服强度具有明显的“Ｒ”特性。利用ＴＥＭ 位错结构分析，阐明了合金微观结构与屈服强度之间的关系，研究结果表明，试验合金所具有的屈服强度随温度的变化规律主要是由不同温度下γ′及γ相内的位错缠结状况、位错对的形态及数量和六面体滑移系的开动程度决定的。

A Ni 3Al based superalloy of Ni Al Mo system has been successfully prepared by using the multifuctional spray atomization and deposition plant.Testing for tensile properties indicated that the spray deposited Ni 3Al Mo alloy possesses “R” characteristic in the yield strength.Analysis of dislocation structure by TEM has revealed the relationship between the microstructure and yield strength.The results show that the yield strength changing with temperature for the alloy is determined by the dislocation winding condition、pattern and quantity of the dislocation pair and starting degree of the hexahedron slide system inside γ′ and γ phases.