Microstructure and properties of die steel fabricated by WAAM using H13 wire

The thin-walled parts with dimension of 260 mm length and 150 mm height were fabricated by wire and arc additive manufacture (WAAM) using H13 wire and Metal-Inert Gas Welding (MIG). The microstructure, hardness, mechanical properties of the parts was studied. It was found that the parts well formed, no clear delineations were observed between layers, different thermal history result in a variety of microstructures. The hardness of the parts was uniform from top to bottom, which was between 300 and 360HV. The mechanical properties of the as welded parts were anisotropic; the horizontal specimen located at the upper had a bigger tensile strength value, while the elongation of horizontal specimen in the middle was highest. The mechanical properties of the parts became isotropic after 830 degrees C annealing for 4 h. Both the test specimens as welded and heat treatment were characterized by dimple-like structures, which indicating a ductile fracture. (C) 2017 Elsevier Ltd. All rights reserved.