1999 年 7 巻 1 号 p. 195-209
The preparation of fine powders by grinding may be accomplished by either a dry or a wet process and the differences between these have been discussed. In general, it is well known that there are many mechanical properties which have direct effects upon the grindabilities of solids. Breaking properties, espe cially, are related to the grindabilities. A practical grinding process involves every breaking condition and these are complex and cannot be measured directly. In addition, the difference in breaking strength in different atmospheres is also known. In this review, bending tests were carried out on glass material in order to investigate the difference between dry and wet grinding. The quantitative effects of water on bending strength and crack propagation on glass surface were studied fundamentally. As a result, it was found that the wet strength is less than the dry, the crack length in water is larger than that in air and a wet grinding process is useful from the point of view of strength of solids.