目的 研究Ni-Al扩散偶在热扩散过程中的微观组织演变规律，提出Ni3Al合金蜂窝形成的模型。方法 采用电镀技术在易加工的Al蜂窝表面电镀一定厚度的Ni，研究热扩散温度和时间对Ni-Al扩散偶组织结构的影响。采用X射线衍射仪对Ni-Al扩散偶进行物相分析;通过扫描电镜技术对Ni-Al扩散偶截面进行形貌及能谱分析，推测微观组织演变规律。结果 热扩散温度为500 ℃时，随着热扩散时间的延长，Ni-Al界面处首先出现NiAl3，然后消失，最终形成以Ni2Al3为扩散层主体、NiAl和Ni3Al为过渡层的多层实心结构;热扩散温度为700、1100 ℃时，Ni-Al扩散偶会分别形成以Ni2Al3、NiAl为内芯，纯Ni为外壳，并以NiAl、Ni3Al薄层过渡的多层中空结构;热扩散温度为1300 ℃时，随着扩散时间的延长，Al相夹心层从Al、NiAl3、Ni2Al3三相混合结构依次转化为成分均一的单相Ni2Al3和NiAl结构，扩散时间继续延长，Ni层随之耗尽，Ni-Al扩散偶最终形成以γ′-Ni3Al为强化相的Ni-Al合金。结论 Ni-Al固相扩散反应过程中，随热处理温度的提升，Al原子发生了明显的外扩散。Ni-Al液固扩散反应过程中，随热处理时间的延长，Ni原子发生了明显的内扩散。在1300 ℃热扩散1 h的条件下，能成功制备Ni3Al基合金蜂窝壁。

The work aims to study the microstructure evolution of Ni-Al diffusion couple in the thermal diffusion process so as to put forward a formation model of Ni3Al alloy honeycomb. Ni was electroplated on the surface of easily processed Al honeycomb so as to study the influence of thermal diffusion temperature and time on the Ni-Al honeycomb microstructure. The phase composition of Ni-Al diffusion couple was analyzed by X-ray diffractometer. The section of Ni-Al diffusion couple was analyzed by scanning electron microscope and energy dispersive spectroscopy technique, and the microstructure evolution of Ni-Al diffusion couple was speculated. Through the analysis of the microscopic morphology, energy dispersive spectrum elements and X-ray diffraction of Ni-Al diffusion couple after thermal diffusion, it was found that NiAl3 appeared in the Ni-Al interface, and then disappeared, therefore a multilayer solid structure with Ni2Al3 as the main diffusion layer and NiAl and Ni3Al as the transition layer formed, with the extension of thermal diffusion time, at a thermal diffusion temperature of 500 ℃. At a thermal diffusion temperature of 700 ℃ and 1100 ℃, Ni-Al diffusion couples formed a multilayer hollow structure with Ni2Al3 and NiAl as the main diffusion layer, thin NiAl and Ni3Al as the transition layer and pure Ni as the shell. At a thermal diffusion temperature of 1300 ℃, with the extension of diffusion time, the Al-phase intermediate layer transformed a three-phase mixed structure of Al, NiAl3 and Ni2Al3 into single-phase Ni2Al3 and NiAl structure with uniform composition in turn. With the diffusion time continuing prolonging, the Ni layer was exhausted. Finally, The Ni-Al diffusion couple formed a Ni-Al alloy with γ′-Ni3Al as the strengthening phase. In conclusion, Al atoms significantly diffuse outward in the Ni-Al solid phase diffusion process with the temperature increasing. Ni atoms significantly diffused inward in the Ni-Al solid-liquid diffusion process with the thermal diffusion time extension. After annealing at 1300 ℃ for 1h, the Ni3Al-based alloy honeycomb is successfully prepared.