Characterization of Residual Stresses in Titanium Alloys

Residual stresses can be introduced and relaxed in aerospace components through manufacturing process steps including machining and thermal processing. These stresses are typically undesirable because they can lead to premature failure and distortion. The prediction of residual stresses in critical components can include modeling and simulation studies; however, materials property data required for these simulations is often lacking. Characterization of residual stresses using X-Ray diffraction can be time-consuming and expensive, and the information returned is limited to surface characterization. Subsurface structures that contribute to residual stresses in machined components are not well characterized. The current study focuses on effective methods of measuring residual stresses that form in titanium alloys after CNC machining and thermal processing. XRD measurements are compared to microstructural features identified using traditional metallographic techniques (optical light microscopy, hardness testing, and electron microscopy). The results of this study provide important materials property data that can be used in future ICME studies.