Effect of deposition parameters on mechanical properties of shaped metal deposition parts

The mechanical properties of Ti-6Al-4V parts fabricated by shaped metal deposition, an additive layer manufacturing technique applying wire-based tungsten inert gas welding, have been measured, with the emphasis of comparing the effect of two different deposition rates. Similar part geometries were obtained for two parts fabricated with deposition rates of 0.1 and 0.3 m/min by adjusting the energy input and the wire feed rate accordingly. This affected the thermal history of the parts, and consequently the morphology, microstructure and mechanical performance. The ultimate tensile strength was between 880 and 1000 MPa, where the strength and hardness were lower for the slower deposition rate. The strain at failure was significantly better for tensile testing perpendicular rather than parallel to the base plate, and considerably larger for the part fabricated with the lower deposition rate. The Young's modulus was comparable for both deposition rates, and independent of the orientation.