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 powder injection molding process. The binder system comprises mainly of natural wax, fatty acid wax, stearic acid, poly-oxi-alkyen-ether and olefin-hydrocarbons. After molding, the binder system was removed by conventional thermal 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 residual carbon level were discussed. A slow heating rate (20 degreesC/h) at the beginning 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 carbon level.