摘要
为研究焊接钢轨轨腰部位残余应力的分布特性,首先阐述了钢轨中残余应力的影响及危害,介绍了盲孔法测量残余应力的原理及优势,采用传统盲孔法与逐层钻孔法分别对标准60kg/m闪光焊焊接钢轨轨腰残余应力进行了对比测试,研究得到了轨腰部位残余应力在母材区及焊缝区的分布特性及沿深度变化的规律。结果表明:轨腰部位母材区的残余应力为压应力,而焊缝区的残余应力为拉应力;轨腰部位的母材区与焊缝区残余应力值的大小相差非常明显,且焊缝区的竖向残余拉应力值很大;在深度h=1mm范围内,轨腰部位的残余应力值随着深度的增大而增大,在0.2mm之后趋于稳定;逐层钻孔法将孔深范围内残余应力分层释放,释放更为彻底,因此逐层钻孔法所测得的残余应力值比传统盲孔法的大。
In order to study the distribution characteristics of residual stresses at the welded rail waist,it introduces the influence and damage of residual stress in rail,presents the principle and advantages of blind hole method for measuring residual stress. Using traditional blind hole method and layer by layer drilling method,it tests the residual stresses in the rail waist of the new standard 60kg/m flash welding rail,obtains the distribution characteristics of residual stress at the rail waist region in the base metal zone and welding zone,finds the law of the variation of residual stress along the depth. The results show that the residual stress in the base metal zone of the rail waist is compressive stress,while the residual stress in the weld zone is tensile stress. The difference of the residual stress between the base metal zone and the weld zone is very obvious,and the vertical residual tensile stress in the weld zone is very large. In the range of depth h = 1mm,the residual stress at the rail waist increases with the increase of depth,and tends to be stable after 0. 2mm. Layer by layer drilling method releases the residual stress in the depth of hole and releases it more thoroughly. Therefore,the residual stress measured by layer by layer drilling method is larger than that of the traditional blind hole method.
出处
《机械设计与制造工程》
2017年第7期82-85,共4页
Machine Design and Manufacturing Engineering
关键词
焊接钢轨
轨腰
传统盲孔法
逐层钻孔法
残余应力
应力分析
welded rail
rail waist
traditional blind hole method
layer by layer drilling method
residual stress
stress analysis
