Effects of debinding parameters on powder injection molded Ti-6Al-4V/HA composite parts

Titanium alloy-hydroxyapatite (Ti-6Al-4V/HA) composite powders produced by a ceramic slurry were mixed with a multi-component binder system in the pow der injection molding process. The binder system comprises mainly of natura l wax, fatty acid wax, stearic acid, poly-oxi-alkyen-ether and olefin-hydro carbons. After molding, the binder system was removed by conventional therm al debinding. The effects of heating rate and gas flow rate on the quality of the debound part in terms of defects, mass of binder removed and residua l carbon level were discussed. A slow heating rate (20 degreesC/h) at the b eginning stage of the debinding step and a higher gas flow rate (250 cm(3)/ min) were required for the production of defect-free parts with minimal car bon level.