Near-net-shape forming of zirconia optical sleeves by ceramics injection molding

Conventional sleeve blanks are currently produced by extrusion, which causes large dimension variations. Consequently it takes longer time and higher cost in the polishing/lapping process to obtain the final dimensions. An injection molding process has been developed for the production of near-net-shape ceramic sleeves. The special designed injection mold has been fabricated to produce sleeve blanks with accurate dimensions. With our zirconia/binder system, the overall debinding/sintering process time is about 26 h for each batch and this provides economic efficiency in mass production. The influence of using recycled feedstock on green body dimensions is investigated thoroughly in this study. By optimizing the process parameters in the molding and debinding stages, one could not only control the dimensional tolerance up to 10 μm (diameter control <0.4% with >99% yield) in blank sleeves but also obtain sintered sleeves with good cylindrical shape. The developed ceramic injection molding process has great advantage in reducing machining time up to 60% in the subsequent grinding/lapping process.