Microstructure and Mechanical Properties of High-Strength, Low-Alloy Steel Thin-Wall Fabricated with Wire and Arc Additive Manufacturing

High-strength, low-alloy (HSLA) steel has attracted much attention in the manufacturing industry because of its good combination high strength and toughness, low cost, formability. Wire arc additive (WAAM) technology can realize rapid prototyping HSLA parts. This study investigated a 26-layer component fabricated with WAAM technique. The microstructure deposited wall ER120S-G is mainly acicular ferrite, there are longitudinal, preferentially growing dendrites along deposition direction. With height accumulation, top sample’s interlayer temperature increases amount ferrite decreases, while quasi-polygonal Widmanstatten increases. changes microhardness were consistent corresponding gradients: sample showed decreasing trend direction, middle was uniform stable. present work shows that mechanical properties parts using have toughness. gradient direction did not lead to significant difference tensile at different heights. On contrary, ductility longitudinal slightly lower than transverse sample, indicating some anisotropy which related directional growth grains heat flow. From current work, thin prepared process properties, indicates it feasible replace traditional processing method rapidly manufacture an structure meeting performance requirements.