The Grindjng Study on the High--hard Sialon Chu Boyi;T. R. A. Pearce;T. D. HowesThe test is carried out on Sialon 101 and 201 with oil and water as grinding fluids. Bascd on the comparation of two grinding fluids some new observation and results were shown in the test. It is also found that the surface damage produced by grinding is mainly controled by cut- ting force and grit size of grinding wheel. No relation was found with higher normal force conducted dy the hydrodynamic pressure when oil is used as grinding fluids. Sialon;;Grinding;;Water, Oil