Investigation of Sinterability of WC-Co Component Comprising of AISI 4340 Steel Inserts

Abstract

In this study, sinterability of WC-9% Co component with AISI 4340 steel insert was investigated using Inserted Powder Injection Molding (IPIM) method. Sintering experiments were performed at temperatures of 1200 °C to 1350 °C with dwell times of 120, 240, 360 min. Defects such as gaps, cracks and macro-porosities were observed in specimens, sintered at temperatures of 1200 °C and 1250 °C for all dwell times. It was proved that sintering temperature of 1350 °C was as high as it caused insert to get deformed and melted. As a result, the optimum sintering temperature and dwell time were determined to be 1300 °C and 240 min, respectively, at which the highest hardness, compression strength, and sintered density were obtained without any defects such as cracks or gaps.

Keywords

• WC-Co feedstock
• AISI 4340 steel
• Sintering
• Inserted powder injection molding

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