砥石結合剤の組成が研削性能に及ぼす影響(第3報)

Abstract

From the result of the previous paper, it has confirmed that the bending strength which is influenced by bonding material composition may be used in place of the traditional standard recommended practice for selection of grinding wheels. And a series of dry surface grinding experiments are carried out on grinding wheels which have the bending strength from 20 to 30 MPa. Then the effect of the bending strength and the percentage of bond or grain on the grinding wheel life are discussed, and the following conclusions are obtained. (1) When the bending strength is higher in the above mentioned range, the normal grinding force increase rapidly, and also, the active grains change into dulling and its life type is burn. (2) If the bonding material composition consist of poor feldspar, the percentage of bond or grain should be increased to obtain the equal bending strength for the grinding wheel which contains rich feldspar in the bonding material and consequently the grinding wheel life becomes short and its life type is often burn. (3) In this case, the effect of percentage of grain on the grinding wheel life is larger than one of bond. (4) The bending strength of grinding wheel is considered to be equivalent to the holding ability of bond for grain in result of the scratching test.