Ni-Al固液扩散偶的组织结构演变及其形成机理-中国有色金属学报.PDFVIP

20 8 2010 8 Vol.20 No.8 The Chinese Journal of Nonferrous Metals Aug. 2010 1004-0609(2010)08-1552-06 Ni-Al / (() 257061) Ni-Al Al Ni Ni-Al /Ni Ni/Ni Al /NiAl /Al+NiAl Ni Ni Al Al+NiAl 2 3 3 3 2 3 3 Ni2Al3 NiAl3 Al NiAl3 NiAl3 NiAl3 Ni-Al ; ; /; ; TG146 A Microstructure evolution and forming mechanism of Ni-Al solid/liquid diffusion couple JIANG Shu-ying, LI Shi-chun (School of Electromechanical Engineering, China University of Petroleum (Huadong), Dongying 257061, China) Abstract: The diffusion couples of Ni/Al were prepared using embedded diffusion couple technology, then, treated at different temperatures between the melting point of Al and Ni for different holding times. The microstructure evolution and forming mechanism of Ni-Al solid/liquid diffusion couple at different temperatures for different holding times were investigated through embedded diffusion couple technology. The results show that the structures of the diffusion couples are Ni/Ni Al /NiAl /Al+NiAl before the Ni substrate is fully consumed. If Ni substrate is consumed completely and heat 2 3 3 3 is hold for some time, Ni Al layer disappears and the structure changes into Al+NiAl . Ni Al layer forms first and is 2 3 3 2 3 only single-phase layer during holding time and NiAl3 layer forms during cooling. The large bulk and small particle NiAl3 precipitate in the Al substrate. A