Cu/V复合中间层对TC4/IN718激光焊接接头组织及性能的影响

Effect of Cu/V multi-interlayer on the microstructure and mechanical properties of TC4/IN718 joint by laser welding

为了实现TC4钬合金与GH4169镍基高温合金的有效连接.采用Cu/V复合中间层对TC4和IN718合金进行连续激光焊接,并分析添加中间层对接头裂纹、组织及力学性能的影响机制.结果表明,常规激光焊接时,TC4/IN718接头焊缝区产生大量Ti-Ni脆性金属间化合物,导致接头形成大量纵向裂纹,焊缝组织为Ti(s,s)+Ti_(2)Ni+Ti-Cr+NiTi+Ni_(3)Ti+Cr(s,s).当采用Cu/V复合中间层后,实现了TC4与IN718合金的有效连接,接头抗拉强度达到271MPa,焊缝组织转变为Ti(s,s)+V(s,s)+NiV_(3)+Cr(s,s)+Cu(s,s)+未熔铜。

In order to realize the effective connection between TC4 and GH4169 alloy,the Cu/V multi-interlayer was applied to join TC4 and IN718 alloy by continuous laser welding.The regulating mechanism of the Cu/V multi-interlayer on the cracks,microstructure and mechanical properties of TC4/IN718 joint was analyzed.The results show that a large number of Ti-Ni brittle intermetallic compounds are generated in the weld area of TC4/IN718 joint with the conventional laser welding,resulting in the formation of a large number of longitudinal cracks in the joint.The microstructure structure of weld zone in the TC4/IN718 joint is comprised of Ti(s,s)+Ti(2)Ni+Ti-Cr+NiTi+Ni_(3)Ti+Cr(s,s).When adopting the Cu/V multi-interlayer,the effective joining between TC4 and IN718 alloy is realized,the tensile strength of the joint reaches 271MP.The microstructure structure of weld zone in the TC4/Cu/V/IN718 joint is transformed into Ti(s,s)+V(s,s)+NiV3+Cr(s,s)+Cu(s,s)+unmelted copper.