INFLUENCES OF METAL CONSTITUENTS TO THE CHARACTERISTICS AND GRINDING ABILITIES OF METAL BONDED DIAMOND WHEEL

This paper describes how the affinity of diamond to metal influences t he holding of abrasive grits by a bond and the chemical reactions amon g metal constituents influence to the mechanical properties of bond. T hese influences to the grinding abilities of wheel are verified experi mentally and qualitatively from the wetting and thermal erosion tests of diamond by metals, the metal sintering and wear test, and the grind ing tests of wheel. A CU-Sn alloy is not suitable for bond due to its large ductility. The durable bond of wheel is expected by diffusing Ni in a Cu-Sn ahoy. The considerable grinding efficiency of wheel is obt ained with diffusing Co and Ti into a Cu-Sn alloy due to their good re activities. The brittle bond of wheel causes from the little reactivit y among Cu-Sn, Ta and Cr. The large quantity of the elasto-plastic fai lure energy of bond provides the increase of grinding efficiency and t he decrease of wheel wear in all kinds of wheel. Consequently, the lar ge grinding ratios are derived by the increase of the elasto-plastic f racture energy which will be one of the estimation factors of wheel gr inding ability.