Ag-28Cu钎焊TA2/BT20接头组织分析

Structure of brazed joints of TA2/BT20 with Ag-28Cu filler metal

摘要: 采用Ag-28Cu钎料对TA2纯钛和BT20钛合金的管板组合构件进行真空钎焊连接试验,分析了不同钎焊温度及保温时间对接头界面结构的影响.结果表明,接头界面结构为BT20/钛基固溶体/Ti₂Cu化合物/银基固溶体+TiCu化合物/Ti₂Cu化合物/钛基固溶体/TA2;随着钎焊温度的升高,银基固溶体和TiCu化合物逐渐消失,Ⅰ区逐渐出现较明显的树枝状生长的组织,分析为Ti₂Cu化合物;随着连接时间的延长,Ti₂Cu化合物逐渐增加,且靠近母材的钛基固溶体层增宽,Ⅱ区最终演变成一个Ti₂Cu反应层.

Abstract: The vacuum brazing of TA2/BT20 titanium alloy was carried out with Ag-28Cu brazing filler metal, and the effects of brazing temperature and holding time on interface structure of the joints were discussed.The experimental results showed that the interface structure consisted of BT20/Ti(s,s)/Ti₂Cu/Ag(s,s) + TiCu/Ti₂Cu/Ti(s,s)/TA2.The Ag(s,s) and TiCu compound decreased gradually with the increasing of brazing temperature and holding time, and then Ti₂Cu compound increased corresponding.And the Ti(s,s) layer gradually became thick.