[Study on grinding of base metal alloys. 5. Constant pressure grinding of a Ni-Cr alloy with electro-deposited wheels].

The grinding techniques and electro-deposited wheels suitable for a 13% Cr-Ni dental casting alloy were determined. The lever-type grinding test machine modified in the previous study was used to investigate the grinding performance of experimental wheels of CBN- and diamond-particles. Depression of the diamond wheel against the work yielded unfavorable grinding results. Not only depression of the wheel against it but also moving the wheel over it with a heavier pressure is desired for higher grinding efficiency and its durability. Probably, the undurability of this wheel is associated with abrasive attrition due to oxidation or some chemical reaction with the work. The CBN wheel had not been suitable for the Co-Cr alloy tested in the third paper, but it exhibited very excellent performance for grinding of the Ni-Cr alloy, even without being moved over the work. Although being high in cost, the CBN wheel may pay for the very high performance and its durability.