K497与FGH741合金的热等静压扩散连接

HIP Diffusion Bonding of Superalloy K497 and FGH741

采用热等静压(HIP)固固扩散连接工艺,研究了K497与FGH741合金经HIP连接及热处理后母材的组织变化、结合界面的组织、力学性能及界面区元素的扩散规律。结果表明,在HIP和热处理阶段,FGH741合金未发生再结晶,其晶粒度与母材基本相同,均为ASTM5～6级;K497合金的粗大枝晶组织和共晶相经热处理后基本消除。结合界面冶金结合良好,形成了一个由亚晶和再结晶晶粒组成的界面区且无有害相析出。结合试样的室温力学性能达到了技术要求,但塑性值偏低。结合界面两侧元素相互扩散的趋势明显。

Superalloy K497 and FGH741 were joined by HIP solid solid diffusion bonding. The microstructure and properties of the mother material, bonded interface and the interdiffusion of the components in the diffusion zone were studied. The results indicated that the recrystallization was not found and the grains size was the same as the mother material, e.g ASTM 5～6 in the superalloy FGH741 after the HIP and heat treatment. The coarse dendrites and the eutectic of superalloy K497 were eliminated mainly after heat treatment. A good metallurgical bonded interface zone, consisting of recrystallization and sub grain bands without TCP precipitate, was obtained .The tensile strength of the bonded specimen met the specification but the ductility was lower. In both sides of the bonded interface, the interdiffusion of components was evident.