GH4169大尺寸合金锻件残余应力试验研究

Experimental Research on Residual Stress of GH4169 Large-size Alloy Forgings

以采用三联冶炼工艺制备并经锻造和热处理后的GH4169合金大棒材为研究对象,基于钻孔法测量原理搭建了高温合金材料小孔法残余应力测试系统,完成了大规格棒材内部残余应力测量试验研究。采用有限元模拟技术对应变释放系数进行标定,结合试验数据计算残余应力并研究应力的分布特征与规律。研究结果表明,有限元标定的应变释放系数与Kirsch理论计算值在材料近表面处存在较大差距,应变释放系数随孔深增加呈现先减少后平缓上升的趋势;GH4169棒材截面残余应力呈现“外压内拉”的分布规律,材料边缘附近残余应力较大,局部区域可达110 MPa。研究结果为残余应力的调控、消减和下游加工工艺优化提供了方向和依据。

Taking the GH4169 alloy large bar prepared by the triple smelting process and after forging and heat treatment as the research object,based on the measurement principle of the drilling method,a small hole method residual stress test system for superalloy materials has been built,and the measurement test research on internal residual stress of the large size bar has been completed.The finite element simulation technology has been used to calibrate the strain release coefficient,the residual stress has been calculated in combination with the test data,and the distribution characteristics and laws of the stress have been studied.The research results show that there is a large gap between the strain release coefficient calibrated by finite element and the Kirsch theoretical calculation value near the surface of the material.The strain release coefficient first decreases and then rises gently with the increase of the hole depth;the residual stress of the GH4169 bar section presents the distribution law of“external pressure and internal tension”,the residual stress near the material edge is relatively large,and that on the local area can reach 110 MPa.The research results provide direction and basis for the adjustment and reduction of residual stress and the optimization of downstream processing technology.