Microstructural evolution of additively manufactured titanium alloys during post-processing heat treatment

Abstract

Conventional titanium (Ti) alloys are of great importance due to their resistance towards carbon footprints and good mechanical and corrosion performance. Additive manufacturing of Ti alloys, especially most common Ti-6Al-4V (Ti6Al4V) alloys, has great potential to be used for biomedical and aerospace applications due to flexible design and less materials waste. However, mechanical performance of additively manufactured Ti6Al4V is inferior to Ti6Al4V alloy manufactured using conventional techniques. In this research, Ti6Al4V alloys manufactured via Electron Beam Melting (EBM) and Selective Laser Melting (SLM) were investigated for microstructural evolution upon varying post-processing heat treatment cycles. Materials and mechanical characterization were conducted using Scanning Electron Microscopy/Energy Dispersive X-ray Spectroscopy (SEM/EDS), and Vickers hardness testing. In this thesis, the relationship between microstructural evolution of additively manufactured Ti6Al4V alloy upon various heat treatment conditions and hardness change was determined.