(中国石油大学(华东) 机电工程学院，东营 257061)
摘 要: 采用镶嵌式扩散偶技术制备Ni-Al扩散偶，在Al熔点和Ni熔点之间的不同温度保温不同时间进行扩散处理。研究Ni-Al固/液扩散偶的组织结构演变及形成机理。结果表明：在Ni基被完全消耗之前，扩散偶的组织结构为Ni/Ni2Al3/NiAl3/Al+NiAl3，Ni基耗完之后继续保温一段时间，Ni2Al3消失，整个扩散偶均由Al+NiAl3的混合组织组成；Ni2Al3层是保温过程中第一个出现的也是唯一出现的连续单相层，NiAl3层则是在冷却过程中形成的；Al基中存在粗大块状和弥散细小状的NiAl3析出相，在NiAl3析出相之间存在无析出区，从界面附近到远离界面，NiAl3析出相和无析出区的尺寸逐渐变小。
关键字: Ni-Al系; 金属间化合物; 固/液扩散偶; 组织结构演变; 形成机理
Ni-Al solid/liquid diffusion couple
（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/Ni2Al3/NiAl3/Al+NiAl3 before the Ni substrate is fully consumed. If Ni substrate is consumed completely and heat is hold for some time, Ni2Al3 layer disappears and the structure changes into Al+NiAl3. Ni2Al3 layer forms first and is 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. At the same time, the non-precipitation zones also emergence because of Ni-poor. From the vicinity of the interface to the distance, the NiAl3 precipitates and the size of non-precipitation zones gradually become small.
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