焊接温度对钛/钢复合管瞬时液相扩散焊接头组织与性能的影响  

Effect of Bonding Temperature on Microstructure and Properties of Transient Liquid Phase Diffusion Bonded Joint of Titanium/Steel Composite Pipe

作　　者：姚尚君 苗鑫 陈思杰[1] 郝丽丽 李振豪 YAO Shangjun;MIAO Xin;CHEN Sijie;HAO Lili;LI Zhenhao(School of Materials Science and Engineering,Henan Polytechnic University,Jiaozuo 454000,China)

机构地区：[1]河南理工大学材料科学与工程学院,焦作454000

出　　处：《机械工程材料》2023年第2期33-38,共6页Materials For Mechanical Engineering

基　　金：河南省教育厅科技攻关项目(14B430002)。

摘　　要：以内衬为TA2工业纯钛、外套为20钢的复合管为研究对象,采用BNi_(2)非晶合金箔为中间层,在氩气保护下,在1130~1200℃焊接温度下对钛/钢复合管进行瞬时液相扩散焊接,研究了焊接温度对钛/钢复合管接头组织和性能的影响。结果表明:不同焊接温度下的接头均成形良好,无孔洞、裂纹等宏观缺陷。随着焊接温度的升高,钛侧焊缝等轴晶组织长大,发生α→α'+β相变,焊缝边界逐渐模糊;钢侧焊缝针状铁素体和珠光体变粗大,黑色脆性相逐渐消失,中间层元素和母材元素的扩散距离增加。不同焊接温度下接头在拉伸时均先在钛侧焊缝处断裂,随着焊接温度的升高,接头抗拉强度先升高后降低,在1180℃时接头抗拉强度最高,为460 MPa,断裂方式为脆韧混合断裂。Taking composite steel pipe with TA2 industrial pure titanium lining and 20 steel coating as the research object,and BNi_(2) amorphous alloy foil as the interlayer,the titanium/steel composite pipe was welded by transient liquid phase diffusion bonding at bonding temperatures of 1130-1200℃under argon protection.The effect of bonding temperature on the microstructure and properties of titanium/steel composite pipe joints was investigated.The results show that the joints at different bonding temperatures were formed well without macroscopic defects such as holes and cracks.With increasing bonding temperature,the equiaxed microstructure of weld at the titanium side grew up,α→α'+βphase transition occurred,and the weld boundary became blurred gradually.The acicular ferrite and pearlite in the weld at the steel side became thicker,the black brittle phase gradually disappeared,and the diffusion distance of elements of interlayer and base material increased.The joints welded at different bonding temperatures all fractured in the weld at the titanium side.With increasing bonding temperature,the tensile strength of the joint increased first and then decreased.When the bonding temperature was 1180℃,the tensile strength was the biggest of 460 MP,and the fracture form was ductile-brittle mixed fracture.

关 键 词：钛/钢复合管 瞬时液相扩散焊 显微组织 抗拉强度 

分 类 号：TG453[金属学及工艺—焊接]