Binder Jetting Of Hardmetals: A Comparative Study Of Microstructures And Properties Of Different Commercial Powders

Additive manufacturing of hardmetals is gaining attention, due to the possibility of fabricating complex shaped parts and new functional designs. Comparing to laser-based AM processes, binder jetting appears to be a more promising technology for hardmetals, due to its low-cost, fast manufacturing process that produces stress and crack-free parts with isotropic properties. In the present work, properties of two different plasma spherodized commercial powders (AMWC701 and AMWC702 grades) have been characterized and printed with binder jetting technology. In addition, final properties of the printed parts sintered in a Sinter-HIP furnace at two different temperatures (1455°C and 1480°C) have been evaluated. Density, shrinkages, microstructure and hardness have been analysed. Best results were obtained with AMWC702 grade sintered at 1455°C, where near full density was obtained (>99%). Measured Vickers hardness was 1227 HV30, which is coherent with the microstructural analysis and close to medium-grained commercial products.