铜作中间层钛与不锈钢的脉冲加压扩散连接(英文)

Impulse Pressuring Diffusion Bonding of Titanium to Stainless Steel Using a Copper Interlayer

采用Cu作中间层对工业纯钛和1Cr18Ni9不锈钢进行了脉冲加压扩散连接。在连接温度850℃,脉冲压力8~20 MPa工艺条件下,在120~180 s时间内即实现了钛与不锈钢的有效连接,与传统扩散焊相比连接时间大幅缩短。在Ti/Cu界面生成了大量的Ti-Cu金属间化合物;而在Cu/不锈钢界面只生成了Cu在奥氏体不锈钢中的固溶体,Cu中间层有效地阻隔了Ti与不锈钢之间的扩散和反应。在连接时间为120 s时得到了最大的连接强度346 MPa。在拉伸载荷下,接头沿Ti/Cu界面发生脆性断裂。脉冲加压扩散连接能在一定程度上降低界面金属间化合物对接头性能的有害作用,提高接头强度,但不能完全消除界面金属间化合物对接头的不利影响。

Impulse pressuring diffusion bonding of commercially pure titanium to 1Cr18Ni9 stainless steel was carried out using a copper interlayer in an attempt to reduce the bonding time and alleviate the detrimental effect of interracial reaction products on bonding strength. Successful bonding has been achieved at 850℃ under a pulsed pressure of 8-20 MPa within a duration of only 120-180 s, which is notably shortened in comparison with conventional diffusion bonding. Microstructure characterization revealed that a sequence of Ti-Cu intermetallic compounds were formed at the Ti/Cu interface and the Cu/stainless steel interface was characterized by the presence of solid solution of Cu in y Fe without any interfacial reaction products. Maximum bonding strength of 346 MPa was obtained when the joint was bonded for 120 s. Upon tensile loading, the joints fractured along the Ti/Cu interracial reaction layer in a brittle cleavage manner, indicating that the impulse pressuring diffusion bonding can alleviate the harmful influence of interracial intermetallic compounds on joint performances to a certain extent, but it is infeasible in completely eliminating the negative effect of the brittle intermetallic compounds.