TiAl/V/Cu/40Cr钢扩散连接界面组织结构对接头强度的影响

EFFECT OF INTERFACIAL MICROSTURCTURE OF DIFFUSION BONDING ON STRENGTH OF THE TiAl/V/Cu/40Cr STEEL JOINT

扩散连接界面组织结构是影响连接性能的关键因素 ,不同的界面组织结构及生成相所决定的接合强度不同。研究了TiAl/V/Cu/40Cr钢的扩散连接 ,结果显示 :在V/Cu及Cu/40Cr的连接界面处出现了对连接性能有利的无限固溶体层 ,而在TiAl/V界面处有金属间化合物层出现 ,接头全部断裂于TiAl/V界面处。TiAl/V界面生成的金属间化合物V5Al8脆性相严重弱化了接头性能 ,使接头强度仅为 2 0 0MPa。

Interfacial microsturcture of diffusion bonding affects intensively performance of joints,and different interfacial microstructure and reaction phase will bring out different strengths of joints.The test results of diffusion bonding of TiAl/V/Cu/40Cr show that layers of infinite solid solutions can be found at the V/Cu and Cu/40Cr interfaces which are favorable to the bonding strength.The formation and growth of the V5Al8 layer arising at the interface leads to a bad performance of joints,with a maximum strength of the joint only 200 MPa.Specimen fractures occur mostly on the interface of TiAl-V.