Influence of Interstitials on Material Properties of Ti6Al4V Produced with Electron Beam Melting

Influence of interstitials on material properties of Ti6Al4V produced with Electron Beam Melting

Arcam has developed the Electron Beam Melting (EBM) technology specifically for cost-efficient production of metal parts. They are manufactured layer-by-layer from metal powder, melted by a powerful electron beam. Each layer is melted to the exact geometry defined by the 3D CAD model. The parts are produced in vacuum at elevated temperatures, resulting in stress-relieved parts with material properties better than cast and comparable to wrought material. With its production-like environment EBM delivers full traceability from ingot to the final part, and do complies with the applicable industry standards for aerospace applications. The process is particularly attractive for titanium and its alloys. EBM is used pre-production of low pressure turbine blades in γ-TiAl since 2010.  

 It is well known that the mechanical properties of Ti6Al4V are affected by the amount of interstitials. From an EBM-specific database containing chemical and mechanical data sets, the influence of interstitials such as iron, oxygen and nitrogen has been extracted with multivariable regression. The results reveal a process with small variations and predictable mechanical properties.  Just as for wrought Ti6Al4V, the tensile strength increases with increasing interstitial concentration.