Manufacturing process for a metal bonded grinding tool and the metal bonded grinding tool produced thereby

Claim 1

In a manufacturing process for a metal bonded grinding tool comprising the steps of (1) preliminary pretreating in which abrasive grains have their surfaces cleaned and prepared for subsequent metal coating, (2) press-forming in which said abrasive grains pretreated in step (1) are press-formed to specified structural dimensions, (3) bond metal coating in which said press-formed abrasive grains obtained in step (2) are placed in a chemical plating liquid and said chemical plating liquid is forcibly passed through the spaces between said abrasive grains, whereby the metal is precipitated on the surfaces of said abrasive grains and said abrasive grains are bonded with said precipitated metal, and (4) heat treating for crystallizing said precipitated metal, the improvement comprising the steps of: a. preparing a rim of porous material formed from a sintered alloy; b. press-forming abrasive grains in contact with said rim of porous material to a specified structural dimension; and c. forcibly passing a nickel chemical plating liquid through and radially out of a contacting body of said abrasive grains and said rim of porous material obtained in step (b) for continuously making the metal precipitate on the surfaces of said abrasive grains, but not completely filling the interstices defined therebetween, and in the pores of said rim of porous material so as to bond said abrasive grains uniformly in an axial direction of said rim and continuously bond said abrasive grains and said rim.