Uncertainty of Additive Manufactured Ti-6Al-4V: Chemistry, Microstructure and Mechanical Properties

Abstract

Ti-6Al-4V is the most common used titanium alloy in aerospace. Parts are therefore often machined from wrought material with high buy-to-fly ratios. Additive manufacturing, however, allows to build parts rapidly and directly from computer-aided design information, offering better material utilisation and lead time reduction. Despite the high potential for aerospace applications, the reliability of the mechanical properties is still at an early stage. This work should give a first overview by determining and comparing DMLS, EBM and DMD Ti-6Al-4V material. Each process is compared based on standardised post treatments, specimen geometries and test methods.It can be seen that the chemistry, the microstructure, and the defect formation differs between the processes, which leads to a scatter in the experimentally determined static tensile, axial fatigue, and crack growth properties.