大型核电厚壁结构X射线衍射法残余应力测试

采用X射线衍射法（ XRD）对大型核电厚壁结构堆芯板端面、堆芯板与吊篮筒体环焊缝焊前焊后残余应力进行无损测量。研究堆芯板端面、环焊缝焊前焊后残余应力的分布情况及变化规律。结果表明：堆芯板焊前残余应力主要是机加工应力，且焊接过程对其残余应力影响不大；1＃和2＃堆芯板环焊缝轴向残余应力分布趋势明显，呈现焊缝为压应力，母材为拉应力；测试的环向应力在各区域分布不一致；焊接对远离焊缝区域的应力没有影响，远离焊缝区域呈现较大的加工应力。

Detection of residual stress in large nuclear thick-walled structure using X-ray diffraction technology

The residual stresses of large nuclear thick-walled structures, including the core plate before and after welding and the welded structure with the core plate and the core barrel shell , were measured with the X -ray diffraction method （ XRD） .The distribution and variation of measured residual stresses have been studied .The results show that the residual stress in core plate end face before welding is mainly the machining stress and the welding process has little effect on the residual stresses in core plate end face ;the trend of axial stresses in two circular welds is similar to compressive stress in the weld and tensile stress in the base metal ; measured hoop stress distributions across the two girth joints vary significantly at different locations; the stresses away from the weld zone are mainly machining stresses .