Optimisation of thermal debinding from injection moulded ceramic parts

A polyethylene-based binder system was used to injection mould SiC thread guides and test rods. The specimens, with wall thicknesses of 3 and 6 mm, had a solids volume content of 54% and 51% respectively. In preparing to remove the binder from the injection moulded parts, a thermal analytical examination of the binder system, its components and the injection moulded bodies was made. In order to determine the shortest time/temperature curve for defect-free debinding, heating/temperature defect diagrams for both were drawn up. Through knowledge of the critical heating rate/temperature relationship, the necessary debinding curves can be set up dependent upon the thickness of the parts. Defect-free debinding of the ceramic pieces is compared to debinding curves of the powder metallurgy.