High-density WC–45Cr–18Ni cemented hard metal fabricated with binder jetting additive manufacturing

Abstract

Additive manufacturing techniques provide alternative methods to the conventional powder metallurgy for the fabrication of difficult-to-be-machined hard metals. Binder Jetting is particularly suitable for the fabrication of crack-free hard metals as compared to other energy-based additive manufacturing techniques since there is no direct high energy heat input during the 3D printing process. To explore the fabrication process of hard metals and their potential applications, high-density crack-free WC–45Cr–18Ni parts were fabricated using Binder Jetting and sintering in this study. The sintering temperature of 1350°C was found to contribute to the best combination of properties with 98.63% density, >1200 HV 0.3 hardness, compression strength >2200 MPa and compressive elastic modulus of 142 GPa. These parts also possess good oxidation resistance, corrosion resistance and dimensional stability. The Binder Jetting fabricated WC–45Cr–18Ni part shows the potential to be applied as mould material working at high temperatures and where corrosion, oxidation and wear resistance are required.

Keywords

• additive manufacturing
• binder jetting
• tungsten carbide
• cemented hard metal
• mould