T2-TA1搅拌摩擦钎焊接头显微组织及结合机理分析

Microstructure and bonding mechanism of friction stir brazing T2-TA1 lap joint

以B-Ag45CuZnCd为中间层进行T2-TA1搅拌摩擦钎焊(FSB)搭接接头的焊接。对两种焊接参数下形成接头的显微组织进行表征。结果表明:在转速为1 500 r/min、焊速为5.7 m/h、压下量为0.3 mm条件下,Ti、Cu界面为"机械混合+冶金结合"的混合机制,焊核区界面由Ti层开始,相组成依次为α-Ti(s,s)+CuTi_2/TiCu/AgCd+Ag(s,s);在转速为1 180 r/min、焊速为9.0 m/h、压下量为0.5 mm条件下,Ti、Cu界面为冶金结合,结合区相组成为Cu(s,s)+Cu_4Ti,过渡层厚度约为8μm;热机影响区界面由Ti层开始,依次由α-Ti(s,s)+CuTi_2/AgCd+Ag(s,s)+Cu(s,s)/Cu(s,s)+Cu_4Ti/Cu(s,s)+Cu_4Ti组成;焊缝边沿区域为完全钎焊结合,界面组织为CuTi+AgCd+Ag(s,s)+Cu(s,s)。

The lap joining of T2 and TA1 were welded by friction stir brazing(FSB) process with B-Ag45CuZnCd interlayer. The microstructure structure were analyzed under two sets of welding parameters. The results indicated that Cu and Ti were bonded by "mechanical mixing and metallurgical bonding" mechanism under rotation speed 1 500 r/min,welding speed 5.7 m/h,heel plug depth 0.3 mm. The interface of the stirred zone was composed of α-T(is,s)+CuTi2/TiCu/AgCd+Ag(s,s). The interface of the Thermo-Mechanically Affected Zone(TMAZ) were consisted of α-T(is,s)+CuTi2/AgCd+Ag(s,s)+Cu(s,s)/Cu(s,s)+Cu4Ti/Cu(s,s)+Cu4 Tiphases. While the edge of the joint was formed by complete brazing zone and the interface was consisted of CuTi+AgCd+Ag(s,s)+Cu(s,s). For the rotation speed 1 180 r/min,welding speed 9.0 m/h,heel plug depth 0.5 mm,Cu and Ti were bonded directly in the interface of the stirred zone and the thickness of the reaction zone was about 8 μm,consisted by Cu(s,s)+Cu4Ti phases.