关键词: 金刚石纤维;陶瓷-金属结合剂;切削;润湿性

Abstract: A new kind of diamond fiber with a certain length to diameter ratio and macroscopic dimensions(1mm×1mm×10mm)by powder injection molding and buried sand sintering method is designed and obtained. The new diamond fiber uses the Na2O-Al2O3-B2O3-SiO2 system ceramics adding a certain amount of iron group metal Co as the diamond abrasive ceramic-metal bond. Different from the traditional diamond grits, this new kind fiber has orderly arrangement in accordance with the requirements and can prepare ordered diamond fiber grinding wheel. Then the flexural strength, hardness and other properties of the diamond fiber are measured, and the contrast test between single diamond fiber specimen and normal ceramic wheel processed ultrahard material SiC enhanced high silicon aluminum alloy is conducted. The results shows that the new diamond fiber prepared has a certain strength and hardness; ceramic-metal bond in the new fiber gives better wet-ability and stronger holding force to the diamond abrasive particle and makes it difficult to fall off; meanwhile, the new diamond fiber has good processing performance and the workpiece has good surface quality, which can achieve precise machining SiC enhanced high silicon aluminum alloy. Effective diamond abrasive particles have a high percentage in the new diamond fibers, and the distribution is uniform. The abrasive particles have a good quality of high uniformity of protrusion height, and have a high utilization with large amount of abrasive particle participated in cutting. Diamond in the diamond fibers realizes three-dimensional arrangement, which means that the lower diamond can continue to play its cutting ability when the upper abrasive loses cutting ability or falls off due to bearing greater friction and extrusion pressure.

Key words: diamond fiber;ceramic-metal bond;grinding;wettability