Measurement of manufacture assembly stresses in thick composite components using a modified DHD method

Understanding of the through-thickness distribution of assembly stresses caused by manufacture process-induced distortion (PID) in thick composite components is essential for safety and reliability assessment. Inspired by deep-hole drilling (DHD) method which is widely used to reconstruct residual stresses in thick metallic components, current research attempts to extend and modify the DHD technique to measure the manufacture assembly stresses in composite components. It is observed that the modified DHD technique can capture the global deformation profiles induced by the assembly stresses, but the previous DHD stress calculation method produces large stress errors. An integrating stress calculation method is then proposed by combining the homogeneous global and the layer-wise antistrophic stress-strain solutions. It is demonstrated that the assembly stresses calculated by the proposed integrating calculation method are significantly improved and it is feasible to measure the manufacture assembly stresses of thick composite components with the modified DHD technique.