Direct energy deposition via arc manufacturing using ultra-low heat input gas metal arc welding

The use of advanced pulsed waveform control during gas metal arc welding is evaluated for additive manufacturing, also known as 3D printing. This investigation used a water-cooled base and a modified wave shape, operating in the short-circuit transfer mode. Carbon steel walls are compared in terms of bead geometry, microstructure and hardness and tensile properties. The results indicate that the use of an ultra-low heat input provides more uniform properties across the wall section and reduces anisotropy in mechanical properties compared to prior work using other gas metal arc welding techniques. Overall, the deposited samples have properties comparable to weld metals produced with ER70S-6 carbon steel wire, with over 600 MPa strength for all conditions tested.