Residual Stress Formation and Relief in Electron Beam Welded Near-Beta Titanium Alloy

Near-beta titanium alloys have been utilized in the aerospace industry due to their exceptional properties, including the high strength-to-weight ratio, excellent corrosion resistance. Electron Beam Welding （EBW), characterized by its high energy density, low heat input, and high precision, has become an ideal choice for welding Ti-alloys. However, the complex thermal cycles and phase transformation brought by the welding process will inevitably induce residual stress, subsequently affecting the structural integrity and fatigue life of components.

Contour method was performed to investigate the effect of EBW process on residual stress distribution, as well as to evaluate the effectiveness of various post-weld heat treatment parameters in relieving residual stress. Additionally, neutron diffraction measurements were conducted to validate the accuracy of the contour method results.

Moreover, a comprehensive analysis was conducted using a range of advanced characterization techniques (e.g., OM, SEM, EBSD, EDS) and mechanical property assessments （e.g., hardness mapping） to explore the effects of the welding process and post-weld heat treatments on microstructural evolution, phase transformation, and mechanical properties. Consequently, correlations between the microstructure and mechanical properties of the welded components were established.