| 摘要 |
PROBLEM TO BE SOLVED: To provide a vitrified super abrasive grain grindstone with small grinding heat generation.SOLUTION: A vitrified super abrasive grain grindstone 26 contains CBN abrasive grains 34 and diamond abrasive grains 36, the diamond abrasive grains 36 have an average grain size of 1/2 to 1/10 of that of the CBN abrasive grains 34, and have a toughness value that is in the range of 0.4-1 with respect to a value of 1 for the CBN abrasive grains 34. The abrasive grain dispersiveness of the CBN abrasive grains 34 is increased by means of such an average grain size of the diamond abrasive grains 36, grinding heat is efficiently absorbed by the grindstone by means of the presence of the diamond abrasive grains 36, which have a high thermal conductivity, and thus the generation of grinding heat is suppressed, suppressing a change in quality of the material 104 subjected to grinding. Also, the diamond abrasive grains 36 have a toughness value in the range of 0.4-1 with respect to a value of 1 for the CBN abrasive grains 34 and have an appropriate frangibility despite having a high Knoop hardness, thus suppressing a decrease in dressability and an increase in working resistance of a super abrasive grain grinding wheel 10 and increasing the durability life of the super abrasive grain grinding wheel 10. |
