Effect of Heat Treatment on the Microstructure and Mechanical Properties of Ti-6Al-4V Produced by Wire Arc Additive Manufacturing

Abstract

The following report investigates the effect of heat treatment on the microstructure and mechanical properties of Ti-6Al-4V produced by Wire Arc Additive Manufacturing (WAAM). WAAM has arisen as a relatively new and successful technology for the production of aeronautical and mechanical components in industry. As a novel concept however, there are many untouched areas of investigation that should be explored to gain a better understanding of the topic. Through this study, the benefits of the different heat treatments and hot isostatic pressing on Wire Arc Additive Manufactured components will be assessed to determine their requirement in to the enhancement of the mechanical properties. The results of this investigation will potentially lead to a competitive solution to post processing WAAM components in an effective manner. Tensile testing was conducted on Wire Arc Additive Manufactured Ti-6Al-4V samples under as built, as built and stress relieved, hot isostatic pressed, vacuum annealed and solution treatment and aged conditions. It was found that the solution treated and aged treatment samples had the most effective tensile results for strength while the vacuum annealed sample demonstrated the best ductility.