| 摘要: |
| 采用Co-Cr-Ni系钎料在不同的钎焊工艺下对DZ40M定向凝固合金进行了真空钎焊试验，通过扫描电镜、波谱/能谱分析仪和X射线衍射仪对钎焊接头进行了微观组织观察和典型物相成分分析，测试了接头的高温持久寿命和高温拉伸强度.结果表明，钎焊接头主要由近缝区、扩散反应区和钎缝中心区组成，近缝区含有较少的化合物，扩散反应区由钴基固溶体、硼化物和碳化物构成，钎缝中心区则由大量的钴基固溶体、白色和灰色硼化物骨架以及少量的深色条块状或骨架状碳化物等构成；在1180℃/30 min钎焊工艺下接头980℃/83 MPa持久寿命最高，平均值达到18 h 10 min，900℃高温拉伸性能均超过母材技术标准规定的305 MPa. |
| 关键词: DZ40M合金 钎焊 组织 性能 |
| DOI： |
| 分类号: |
| 基金项目: |
|
| Microstructure and mechanical properties of DZ40M alloy brazed joint |
|
ZHAO Haisheng, PAN Hui, ZHANG Xuejun, CHENG Yaoyong
|
|
Welding and Plastic Forming Division, Beijing Institute of Aeronautical Materials, Beijing 100095, China
|
| Abstract: |
| Vacuum brazing of directionally solidified superalloy DZ40M was carried out using Co-Cr-Ni filler metal under different brazing parameters. The corresponding microstructure of the joint was investigated by means of SEM, WDS/EDS and XRD, and the high temperature creep rupture life and tensile strength was measured. The results show that the typical joint was mainly composed of base metal near the brazed seam, diffusion-reaction zone and the central zone. There were a few compounds in the base metal near the brazed seam. The diffusion-reaction zone was made up with Co-base solid solution, carbides and borides. The central zone consisted of Co-base solid solution, gray borides and a small quantity of dark strips of carbides. The joint brazed at 1 180℃ for 30 min had the longest average creep rupture life tested at 980℃/83 MPa, which was 18 h 10 min. The tensile strength of all brazed joints tested at 900℃ were all higher than 305 MPa which is the technical standard value of base metal. |
| Key words: DZ40M alloy brazing microstructure mechanical property |
