Effects of Sinter-HIP Temperature on Microstructure and Properties of WC–12Co Produced Using Binder Jetting

Abstract

This study investigates the influence of different sinter-HIP temperatures and binder saturation levels on the microstructure and properties of WC–12Co cemented carbide, produced using binder jetting. The sinter-HIP process was performed at 1400 °C, 1460 °C, and 1500 °C and binder saturation levels of 60% and 75% were selected during printing. The binder saturation proved to affect the repeatability of the manufacturing process and the sturdiness of the green models. The increase of the sintering temperature from 1400 °C to 1460 °C is correlated with an increase in the density. Nonetheless, a further raise in temperature to 1500 °C leads to significant grain coarsening without clear advantages in terms of porosity reduction. Both the transverse rupture strength and Vickers hardness increase when the sinter-HIP temperature rises from 1400 °C to 1460 °C, where the typical results for traditionally manufactured WC–12Co are met, with a comparable grain size. The transverse rupture strength and Vickers hardness then decrease for samples treated at 1500 °C. Finally, potential issues in the manufacturing process are identified and correlated with the defects in the final components.

Keywords

• cemented carbides
• binder jetting
• additive manufacturing
• sinter-HIP
• WC-Co
• microstructure