摘要
本文对不同粒径氩气雾化镍基高温合金粉末(AA粉)的凝固组织进行了研究。结果表明:AA粉表面和内部主要为树枝晶和胞状晶组织,块状碳化物相在晶界和晶内析出。随着粉末粒径的减小,冷却速率增大,组织由树枝晶向胞状晶转变;粉末内部的气孔、缩松明显变少且尺寸减小;基体γ相点阵常数增大;显微硬度上升。
The microstructural characteristics of an argon gas atomized(AA) nickel-based superalloy powders with different sizes were investigated.The surface and interior of the powders exhibit a typical dendritic and cellular solidification microstructure.Carbides precipitated in the interior or grain boundary regions.With the particle size decreasing,the microstructure of particles changes from the dendritic to cellular structures.The gas pore or interior shrinkage of the powder decreased,and the lattice constant of γ phase and the micro — hardness of powders increased.
引文
[1]曲选辉,张国庆,等.粉末冶金技术在航空发动机中的应用[J].航空材料学报,2014,34(1):1~10.
[2]汪武祥,何峰,等.粉末高温合金的应用与发展[J].航空工程与维修,2002(6):26~28.
[3]李周,张国庆,等.氩气雾化高温合金粉末的制备及其组织与性能[J].中国有色金属学报,2005,15(2):335~338.
[4]周玉.材料分析方法[M].第二版.北京:机械工业出版社,2004.
[5]吴凯,刘国权,等.含Hf和Ta新型镍基高温合金粉末中碳化物相[J].北京科技大学学报,2010,32(11):23~32.
[6]Roger C Reed.The Superalloys:Fundamentals and Applications[M].Cambridge University Press,2008.
[7]许文勇.喷射成形高温合金组织特性及变化规律的研究[D].北京:中航工业北京航空材料研究院,2008.