(1. 吉林大学 材料科学与工程学院,长春130025;
2. 长春工程学院 机电学院,长春 130012;
3. 吉林大学 地面机械仿生技术教育部重点实验室,长春130025)
摘 要: 研制一种适合钎焊立方氮化硼与45钢异质材料的新型高温BCu80Ni5SnTi活性钎料,采用SEM、EDS及XRD对BCu80, Ni5SnTi系活性钎料的微观组织及钎焊接头力学性能进行研究。结果表明:适合钎焊c-BN的活性钎料成分为Cu78~81Ni5~6Sn3~5.5Ti10~12(质量分数,%),固相线温度为858.4 ℃,液相线温度为874.8 ℃;钎料组织由α-Cu固溶体、Ni固溶体、Cu-Sn共晶及少量Cu4Ti3、Cu3Ti2、Cu3Sn、CuSn和Ni17Sn3等化合物组成;该钎料对c-BN的润湿性较好,润湿角为28˚~30˚,钎焊c-BN与45钢的接头强度为210~230 MPa;新型钎料钎焊冶金特性较好,钎焊接头界面实现冶金结合。
关键字: CuNiSnTi;立方氮化硼;活性钎料;真空钎焊
(1. School of Materials Science and Engineering, Jilin University, Changchun 130025, China;
2. School of Mechatronies Engineering, Changchun Institute of Technology, Changchun 130012, China;
3. The Key Laboratory for Terrain-machine Bionics Engineering, Ministry of Education,
Jilin University, Changchun 130025, China)
Abstract:A new-type BCu80Ni5SnTi filler metal suitable for brazing cubic boron nitride (c-BN) and 45 steel was prepared. The microstructures of BCu80Ni5SnTi active filler metal and mechanical properties of the joints of c-BN and 45 steel brazed with BCu80Ni5SnTi filler metal were analyzed by SEM, EDS and XRD. The results show that the solidus and liquidus temperatures of the novel BCu78-81Ni5-6Sn3-5.5Ti10-12(mass fraction, %) active filler metal are 858.4 and 874.8 ℃, respectively. The microstructure of the filler metal mainly consists of α-Cu solid solution, Ni solid solution, Cu-Sn eutectic phase as well as a little Cu4Ti3,Cu3Ti2,Cu3Sn,CuSn and Ni17Sn3 compounds. The wettability of the filler metal on c-BN is good and the contact angle is about 28˚−30˚. The shear strength of the brazed joint between c-BN and 45 steel using this active filler metal reaches 210−230 MPa. The new-type BCu78-81Ni5-6Sn3-5.5Ti10-12(mass fraction, %) active filler metal possesses better brazing metallurgy characteristics. Chemical metallurgic joining forms in the interface between c-BN grits and BCu80Ni5SnTi active filler metal.
Key words: CuNiSnTi; cubic boron nitride; active filler metal; vacuum brazing