航空用钛合金激光焊和TIG焊残余应力测试

TEST OF RESIDUAL STRESS IN LASER BEAM WELDING AND TIG WELDING JOINTS OF AERONAUTICAL TITANIUM ALLOY PLATE

钛合金是重要的航空材料。采用小孔释放法对钛合金平板激光焊接和钨极氩弧焊 (TIG)残余应力进行了测试研究 ,分析了焊接方法及焊接热输入和焊后热处理对残余应力分布规律的影响。研究结果表明 :在热影响区内 ,激光焊接残余应力分布规律与普通熔焊方法相似 ,但其分布区域较窄 ;与TIG焊相比 ,激光焊残余应力值大约低 10 0MPa;焊后热处理能显著降低残余应力并使其分布区间平缓。

Titanium alloys are important aeronautical material. Hole-drilling method is used to measure the residual stress in laser beam welding (LBW) and TIG welding joints of titanium alloy plate. The effects of different welding technologies, heat input and post-weld heat treatment on residual stress distributions are analyzed. In HAZ, the distribution of laser welding residual stress is similar to that of traditional fusion welding means, but the zones of distribution are much narrower. Compared to that of TIG welding, the values of laser welding residual stress are lower about 100MPa. Post-weld heat treatment will relieve residual stress efficiently and make its distribution range gentle.