On the WAAM characteristics of oxide-modified H13 solid wire by MAG process

Abstract

In order to meet weld needs of the H13 hot-work molds, commercial solid wires are generally the pseudo ones by decreasing carbon and increasing chromium. It results in a non-ideal performance for the repaired molds. In this study, one kind of solid wire was prepared by using the oxide-modified H13 steel. Using this solid wire, a 6-layer 13-pass H13 steel was additively manufactured by the MAG process. Different from similar results reported, the deposited H13 steel mainly consisted of lower bainite, together with some martensite and retained austenite, and showed narrow variation in hardness due to the absence of apparent δ-F phase in the overlap zones between the weld passes. Though there existed some difference in mechanical properties along different directions, this difference was less than what was reported by others. Tempering at 565 °C could improve its mechanical properties, the optimum tensile strength of 1798 MPa (26% higher than that by CMT technology), V-notch impact toughness of 18.3 J/cm2, and better wear resistance with less coefficient of friction (COF) of 0.45 and volume loss (VL) of 0.285 mm3 were obtained in the tempered steel. With a little increase in the tensile strength, its impact toughness is about 96% higher, and COF and VL are about 12% and 14% lower, respectively, than those without tempering. All these results proved that the oxide-modified H13 solid wire exhibited good WAAM characteristics and introduction of nano-oxide particles is effective for preparing real H13 solid wire with high performance.

Keywords

• WAAM
• MAG process
• H13 steel
• Oxide particle
• Strengthening-toughening