| With high hardness, high abrasive resistance, good biocompatibility and chemistry stability and so on, alumina ceramic has been considered as an excellent material for making artificial joints. However, the extensive applications were limited due to its hard and brittle properties that brought great difficulties in manufacturing. In this paper, high efficiency and economic manufacturing means were studied for industrial production of the alumina ceramic femoral head prostheses. By the way of the numerical control machining, the optimization related to preparation, process, automatically programming and cutting parameter were studied.Firstly, high pure a-Al2O3 and MgO-ZrO2 (Y2O3) composite additives were mixed with the method of the ammonia precipitating-enwrapping. After dehydrating, drying and calcinating, the powder with good sintering activity was acquired. The ceramic green was shaped by pressing and cold isostatic pressure, then an uniform and compact ceramic green was produced. The ceramic green was pre-calcined at 1150 C to have proper strength for machining and then the femoral head prostheses on the basis of the required design drawing was shaped through precisely turning on the NC lathe. The shaped prostheses was sintered at 1600 C for 2.5 hours in an electrical furnace. Finally, the surface of the alumina femoral head was ground and polished, which made the surface reaching the degree of approximate mirror finish and matching the femoral stem well.Based on the Pro/Engineer-a software for Computer Aid Design and Manufacture the automatic programming system for the specific NC machine was developed, so the integration of design and machining can be realized. First of all, those features from CAD/CAM manufacturing model were chosen for generating machining track. Then the process and outcome were simulated on the screen. Finally the NC codes were generated after post process and the automatic programming was completed. NC Machine's utilization ratio as well as yield was enhanced by this CAD/CAM integration technique.The relationships between the presintering process including the ratio of heating-up, presintering temperature and holding time to alumina and the machiningperformance of its presintered briquet were studied respectively. The alumina briquet was acquired which was presinetered at 1150 C, 2 hours holding time and heating-up curve with several heating-up ratios, and which could avoid rapture or breaking when machined. The machining experiment has been studied to the briquet presintered at 1150 C. The machining cost related to cutting parameters, such as shaft speed, feedrate and cutting depth has been discussed. Then the best cutting parameters have been obtained which led to the least cost.From above study, it would be concluded that the NC machining can meet the request of industrialization of femoral head prosthesis for alumina ceramic.
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