纳米镍粉在钛合金-不锈钢扩散焊接中的应用

Application of Nickel Nano-particles in the Diffusion Bonding of Titanium Alloy and Stainless steel

采用恒温恒压扩散焊、相变超塑性扩散焊、冲击加压扩散焊对直接对焊和加纳米镍粉中间层的钛合金-不锈钢焊接接头进行了研究。测试了接头强度,并进行了断口形貌观察和组织分析,结果表明:3种试验方法中,恒温恒压扩散焊所得接头强度较小,而冲击加压扩散焊所得接头强度较高;直接扩散焊时,接头上两种基体材料之间的互扩散程度很大程度上影响了钛合金-不锈钢接头的强度;采用纳米镍粉作中间层能形成强度较高的接头,达到了213MPa,但纳米镍粉的致密度不够高,接头的强度在很大程度上受到了限制。

Direct diffusion bonding and nickel nano-particles layer diffusion bonding of titanium alloy-stainless steel were investigated by diffusion welding at constant temperature and pressure, diffusion welding under pulsatile pressure and phase transformation super-plastic diffusion welding. Result gained by rigidity testing, rupture observation and micro-structure analysis showed that the strength of bonding gained by diffusion welding at constant temperature and pressure is lower, while the joint obtained by diffusion welding under pulsatile pressure is higher. The degree of diffusion in direct welding affected the strength of the bonding greatly. Better joint was gained by diffusion welding with nickel nano-particles layer, with its strength up to 213 MPa, but the density of the nickel nano-particles layer is not high enough, which limited the strength of the joint.