钛合金和不锈钢的扩散焊接

Diffusion welding of titanium alloy and stainless steel

对TA17钛合金与1Cr18Ni9Ti不锈钢的焊接接头强度进行了实验研究。采用恒温恒压扩散焊、相变超塑性扩散焊和脉冲加压扩散焊实现了钛合金和不锈钢的焊接,测试了焊接接头的强度,并对接头进行了金相观察。结果发现:3种接头的强度都达到了264MPa,且接头为多层次的多相组织。物相分析发现钛合金不锈钢接头中存在Fe2Ti和σ (FeCr)两种脆性金属间化合物。脉冲加压扩散焊能促进扩散过程,减少金属间化合物的形成,改善其分布,是一种较有前景的扩散焊方法。

The strength of welding joint between titanium alloy TA17 and stainless steel 1Cr18Ni9Ti was investigated. Bonded joint was obtained by diffusion bonding at constant temperature and pressure, phase transformation superplastic diffusion bonding and diffusion bonding under pulsatile pressure. The strength of welding joint was tested and metallography of welding joint was observed. The results show that the strength of joints obtained by three diffusion welding are all up to 264 MPa and there are several different layers in the joint. Phase analysis shows that there exist brittle Fe_2Ti and σ -(FeCr) in the titanium alloy-stainless steel joint. Diffusion bonding under pulsatile pressure is an ideal bonding method, which can accelerate diffusion, reduce the amount of intermetallic compound and improve its distribution.