X-ray high temperature in-situ stress measurement of fiber or powder reinforced plastic materials

X射线sin^2应变法应力测量是检测工业产品中残余应力的有效手段之一。在这项研究中，钨纤维增强聚乙烯复合材料中的残余应力进行了检查，通过X射线应力测量技术。采用透射衍射法测量聚乙烯基体的残余应力。在测量残余应力之前，估算了复合材料基体高密度聚乙烯（HDPE）的X射线弹性常数。透射法正弦图在不同拉伸载荷下均呈现良好的线性关系。在此基础上，研究了HDPE基体相复合材料中的残余应力。从测试结果来看，HDPE基体中纤维的纵向残余应力为拉应力，横向残余应力为压应力。

X-ray stress measurement with sin^2Ψ method is one of useful tools to detect residual stresses in manufactured products. In this study, the residual stresses in the tungsten fiber reinforced polyethylene composite were examined by X-ray stress measurement technique. The transmission diffraction method was employed in residual stress measurement of polyethylene matrix. The X-ray elastic constant of high density polyethylene (HDPE) which formed matrix of the composite was estimated before residual stress measurement. The results of sin^2Ψ diagram with transmission method show good linearity under the several tensile loading. After that the residual stresses in the composite were investigated for HDPE matrix phase. From the measurement results, the tensile residual stresses existed in fiber longitudinal direction and compressive ones in transverse direction for HDPE matrix.