| 摘要: |
| TA15钛合金与K4648高温合金异质连接件可用于航空航天发动机部件，对实现发动机轻量化及提高推重比具有重要意义。采用Au-17.5Ni (wt.%)钎料对TA15钛合金与K4648高温合金异质金属进行钎焊，研究了钎焊接头的界面组织与形成机制，分析了钎焊温度与保温时间对接头组织与性能的影响。结果表明，钎焊接头的典型组织为：TA15/β-Ti+Ti2Ni+Ti3Au/Ti2Ni+Ti3Au/富Ti相/Ti-Cr-Ni三元Laves相/(Cr, Ni)固溶体/K4648。液态钎料中的Au、Ni元素向两侧母材中扩散，同时TA15一侧母材溶解，大量Ti元素与钎缝中的Au、Ni反应，在TA15界面生成β-Ti与Ti3Au、Ti2Ni共析组织；溶解的Ti元素扩散至K4648界面富集并与Cr、Ni反应，生成Laves相反应层；当使用AuNi钎料在1000 ℃保温10 min时，接头拉剪强度最高为72 MPa。 |
| 关键词: TA15 AuNi钎料 钎焊 K4648 |
| 基金项目:国家自然科学基金（523***24；5222****003） |
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| Microstructure and Properties of TA15 and K4648 Joint Brazed with AuNi Filler Alloy |
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Sun Liangbo1,2, Liu Chunfeng1,2, Wang Yansong1, Li Zengwei1, Wang Shuohao1, Zhang Jie1,2
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1. School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001;2. Center of Analysis and Measurement, Harbin Institute of Technology, Harbin 150001
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| Abstract: |
| TA15 titanium alloy and K4648 superalloy hetero-joint can be used in aerospace engine components, which is of great significance to realize engine lightweight and improve thrust-to-weight ratio. TA15 and K4648 were brazed with Au-17.5Ni (wt.%) filler metal. The interface microstructure and formation mechanism of brazing joint were studied. The effects of brazing temperature and holding time on the microstructure and mechanical properties of the joint were analyzed. The results show that the typical interfacial microstructure of brazing joint was TA15/β-Ti+Ti2Ni+Ti3Au/
Ti2Ni+Ti3Au/Ti-rich phase /Ti-Cr-Ni ternary Laves phase /(Cr, Ni) solid solution /K4648. The Au and Ni elements in the liquid filler diffused into the substrates on both sides, and the eutectoid structure of β-Ti with Ti3Au and Ti2Ni was formed at the interface of TA15. At the same time, the TA15 was dissolved into the liquid filler at the interface, a large amount of Ti elements reacted with Au and Ni in the brazing joints to form Ti2Ni and Ti3Au. The dissolved Ti element was enriched at K4648 interface and reacted with Cr and Ni to form Laves phase. The maximum shear strength of the joint was 72 MPa when the brazing parameter was held at 1000 ℃ for 10 min. |
| Key words: TA15 AuNi filler brazing K4648 |
