Micro-powder injection molding (μPIM) of tungsten carbide

Tungsten carbide (WC) is a well-known hard alloy material due to its hardness, resistance to wear and extensive applications. The current demand for WC in micro-applications is continually increasing. The production of micro-WC-10%Co parts through micro-powder injection molding (mu PIM) technique is challenging for researchers. The thermal phenomenon plays a significant role during the mu PIM of WC-Co due to its outstanding thermal conductivity. The heat transfer involved in the microinjection molding (Model: DSM explore) of WC-10%Co in this study is illustrated and highlighted. The mold temperature is demonstrated to influence microinjection molding due to the high thermal conductivity of WC-10%Co. A higher surface area-to-volume ratio of 1.25:1 is beneficial in the debinding process, in which the majority of the soluble organic binder is lost within the first 5 min. WC-10%Co sinters in the temperature range of 1380-1420 degrees C with a dwell time of 2 min during liquid phase sintering (LPS). The sintered part exhibits a densification of 96% of the theoretical density, a hardness of 1700 kg/mm(2), a bending strength of 2100 MPa and a surface roughness of 1.17 mu m. The consequential effect of the injection parameter by type and characteristic of powder during micro-powder injection molding are determined. (C) 2014 Elsevier Ltd. All rights reserved.