振子型結合度試験機による研削砥石結合度の測定 第一報 : 合金工具鋼及び超硬板バイトによる, A砥粒ピトリファイドボンド砥石の系列的な結合度表示について

Abstract

In this report, the grade of grinding wheels by swing arm type grade tester are shown. This tester is constructed of the mechanism to swing down the pendulum hammer with a plate cutting tool about an axis from a definite height, to scratch the surface of a grinding wheel by a cutting tool edge, and to measure the scratching energy. The grade of grinding wheels are indicated by this scratching energy. When the cutting tool is made of cemented carbide alloy, the grade of A-grain vitrified wheels are wholly indicated from #24 to #120 without influence of the abrasion of cutting tool edge. Then, this scratching energy can be converted into the hardness numbers or grading letters of the alphabet, by using an experimental equation. The equation is as follows; E=C・(H^<1.83>)・(1.12^Z)・(G^<0.925>), Where E=scratching energy being measured, kg-m. H=depth of cut from the suface of grinding wheels, mm. G=grain size of grinding wheel being indicated by standard screen number. C=constant being varied by the shape and the hardness of cutting tool edge, and, in this case, equals to 1.42×10^<-4> Z=The order number of grade of the wheel bond