在真空环境下采用Ni-Si-B中间层,扩散钎焊DZ38G高温合金,扩散连接温度为1050℃,扩散连接时间为30～70 min,焊后均质化保温温度为1050℃,保温时间为300 min。研究了接头的微观结构。研究表明:等温凝固完成前,接头主要有四种不同的相构成:初始共晶的γ固溶体、Ni基硼化物、共晶的γ固溶体和母材金属;在1050℃下,扩散钎焊时间70 min以上,可完成等温凝固。 Under vacuum environment, the Ni-Si-B intermediate layer was used to diffuse and braze the DZ38G superalloy. The diffusion connection temperature was 1050 ℃, the diffusion connection time was 30 to 70 min, the homogenization holding temperature after welding was 1050 ℃, the holding time was 300 min. The microstructure of the joint was studied. The results show that there are four main phases in the joint before the isothermal solidification: initial eutectic γ solid solution, Ni boride, eutectic γ solid solution and base metal; at 1050 ℃, diffusion brazing time 70 min or more, to complete the isothermal solidification.