一、前言 SFG-2 是一个高强度铸造镍基高温合金,具有优良的热强性能,用作708工程915发动机一级涡轮叶片材料。它成份复杂,组成相较多,它们在高温长期使用过程中往往发生如聚集、长大、溶解、析出、分解、相互转变等种种变化,这对合金的机械性能将产生一定影响。特别是在一般高强度铸造镍基合金中高温长期加热后经常出现对性能相 I. Introduction SFG-2 is a high-strength cast nickel-base superalloy with excellent hot-strength properties and is used as a first-class turbine blade material for the 708 Engineering 915 engine. Due to its complicated composition and relatively large composition, many changes such as aggregation, growth, dissolution, precipitation, decomposition and mutual transformation often occur during long-term use at high temperatures, which will affect the mechanical properties of the alloy to a certain extent. Especially in the general high-strength cast nickel-based alloy after high temperature long-term heating often appear on the performance phase