摘要: This project deals with the development of advanced manufacturing technologiesfor finishing silicon nitride balls and rollers for bearing applications. Magnetic field assisted polishing was used for finishing the balls and magneti... 展开 This project deals with the development of advanced manufacturing technologiesfor finishing silicon nitride balls and rollers for bearing applications. Magnetic field assisted polishing was used for finishing the balls and magnetic abrasive finishing for finishing rollers. By applying low levels of controlled force (1 N/ball or less) the damage on the finished surface is expected to be minimal. Also chemo-mechanical polishing was used to minimize the brittle fracture. Using these techniques the polishing time was reduced from some 10-20 weeks to about 20 hours. The finish obtained was about 5-10 nm and the sphericity in the range of 0.5 -1 micrometer. In this report various technical papers dealing with various aspects of the finishing of silicon nitride balls and rollers prepared on this contract are included as appendices. They include the technology of polishing, optimum polishing conditions, the thermal model of the spot temperature generated in polishing, and finally the material removal mechanisms in polishing. 收起