焊趾TIG重熔层激冷处理后残余应力场有限元分析

FEA of the residual stress field of TIG remelted layer at weld toe after chilling treatment

用有限元法计算了焊趾TIG重熔及激冷处理后对接接头的残余应力场,并采用盲孔法测试了焊趾部位的残余应力值计算和测试结果表明:焊态下及焊趾TIG重熔后,焊趾处均为残余拉应力,而对TIG重熔层进行喷淋激冷处理后,则形成残余压应力场。从而可通过改进焊趾TIG重熔工艺,来进一步提高机车车辆转向架等焊接结构的疲劳强度。

The residual stress field of the butt joint after weld toe TIG remelting and chilling treatment is calculated with FEA while the residual stress value at the weld toe is tested with blind-hole method. The calculation and testing results indicate that residual tensile stress is detected at the as-weld weld toe after TIG remelting treatment, and the residual compressive stress is created after water-spraying chilling treatment on the TIG remelted layer. This paper concludes that the fatigue strength of the welded structures such as bogies for locomotive ＆ rolling stock can be further enhanced by improving TIG remelting proces- ses for weld toe.