钛/铜中间层/钢扩散焊复合管界面组织与性能

Microstructure and properties of diffusion bonded interface of titanium-copper interlayer-carbon steel composite tube

以铜箔为中间层,采用拉拔—内压扩散法制备钛/钢复合管.利用光学显微镜、扫描电子显微镜、X-光衍射仪和能谱仪对界面组织、断口形貌和成分进行分析,通过剪切试验测定界面的结合强度.结果表明,以铜箔作中间层,拉拔—内压扩散法实现了钛/钢的冶金结合;在钛/铜界面处发生了明显的原子扩散,并形成不同的扩散层;随着扩散温度和时间的增加扩散层的厚度逐渐增加;中间层的加入阻止了固相扩散中钛铁、钛碳脆性化合物生成;钛/钢界面的抗剪强度随着扩散温度的升高先增加后降低,铜层的加入使抗剪强度明显提高,最高可达310 MPa.

The composite tube of titanium/steel was prepared by the drawing and inner pressure diffusion technique by using Cu foil as an interlayer.The interface microstructure,fractured surface and components were investigated with OM,SEM,XRD and EDS.The bonding strength of the interface was studied by shear test.The results show that the metallurgical bonding of titanium and steel was obtained by the drawing and inner pressure diffusion technique with copper foil as an interlayer.The interface components analysis show that the elements diffusion was found between the titanium/copper interface and the diffusion layer was formed.The thickness of the diffusion layer increased with increasing of diffusing time.The Fe-Ti brittle compound was prevented by using copper interlayer at lower diffusion temperature.The shear strength of titanium/steel interface firstly increased and then decreased with diffusion temperature increasing.Copper interlayer can improve the shear strength significantly,and the maximum shear strength can reach 310 MPa.