Ti—Al—Si对SiCp/Al基复合材料等离子弧焊焊缝的组织与性能的影响

Influence of Ti-Al-Si on microstructures and mechanical properties of weld in plasma arc "in-situ" welding of SiCp/Al MMCs

以Ti-Al-Si合金作为合金化填充材料,用氮氩混合等离子气体对SiCp/Al基复合材料进行等离子弧原位焊接,研究了Ti-Al-Si对焊缝的组织和性能的影响.结果表明:填加Ti-75Al-5Si合金时,熔池中Si和Ti的联合作用有效抑地制了针状脆生相Al_4C_3的生成,形成了稳定的熔池,得到了以TiN、AlN、TiC和Ti_5Si_3等为二次增强相的焊缝.焊缝的组织致密,结合良好,其最大拉伸强度为225 MPa.

Contrasting with that adding Ti-Al alloy, the present work investigated the influences of Ti-Al-Si on microstructures and mechanical properties of weld produced by plasma arc ＂in-situ＂ weldalloying welding of SiCp/Al MMC with argon-nitrogen mixture as plasma gases and Ti-Al-Si alloy as filled composite. The results show that the formation of needle-like harmful phases Al4C3 are effectively inhibited by the joint role of [Si] and [Ti] adding Ti-75Al-5Si alloy sheet filler. The stable molten pool was gained, and the mechanical properties of joint is effectively enhanced due to the compact-grain structure and the second reinforced composites of welded joint such as TiN, AIN, TiC, Ti 5Si3 etc. The test results of mechanical property show that the maximum tensile strength of welded joint gained with Ti-Al-Si alloy as filled composite is 225 MPa.