Microstructure and properties of additive manufacturing by gas-shielded arc welding with hydrogen-resistant steel wires

The hydrogen steel gas-shielded welding wire was utilized in the WAAM technique, and the microstructure, crystal structure, and properties of the parts generated by layer-wise deposition were analyzed and evaluated. The study revealed that the components exhibit good quality, devoid of significant defects, and demonstrate robust internal metallurgical bonding. The metallographic structure mainly consists of pearlite and ferrite. The distribution of microhardness in the parts is fairly consistent, with mean microhardness values of 196.6 HV_0.1 (transverse) and 196.7 HV_0.1 (longitudinal). The parts exhibit exceptional mechanical properties, with a transverse yield strength of 406 MPa, an elongation rate of 14.2%, and a longitudinal yield strength of 380 MPa, an elongation rate of 18.9%. At − 30 °C, the average transverse Charpy impact value is 95.7 J, and the average longitudinal is 117 J.