Powder injection moulding has long been known as a useful tool in fabricating parts with high precision in high-capacity mass production. During the process, removal of the organic vehicle is frequently recognized as a time-consuming and less cost-effective stage, and solving this problem has been an important and interesting objective for many investigators to date. An improper binder removal strategy deteriorates the green microstructure and, in consequence, the final sintered products to a signifi-cant extent. Recently, many techniques, such as pyrolysis debinding [1], solvent extraction [2], powder bed extraction [3,4] and supercritical extraction [5], have been developed in order to effectively remove organic binder and obtain green compacts with a uniform and defect-free micro-structure. This, according to the principle of sintering, should offer better sinterability, and a fine, fully dense sintered compact may usually be expected. Among those techniques, thermal pyrolysis is the most frequently used method to remove organic binder. Basically, the binder is removed by three mechanisms, namely evaporation, thermal degradation and oxidative degradation [6].
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