Vitrified bond grinding wheel and process for producing the same

Abstract

In a vitrified bonded grinding wheel having superabrasive grains 11 such as CBN, diamond or the like bonded with a vitrified bond 12 , pores 16 of the vitrified bonded grinding wheel has impregnated thereinto a resin 17 consisting of any resin selected from, e.g., unsaturated polyester, vinyl ester and allyl ester which are in a liquid state at the normal temperature and which have a thermosetting property, and being capable of radical polymerization. Thus, any separation gas or the like is not generated when the impregnated resin is hardened, whereby the strength of the grinding wheel can be enhanced.

1 - 4 . (canceled) 
   
   
       5 : A vitrified bonded grinding wheel comprising superabrasive grains selected from CBN and diamond bonded with a vitrified bond, wherein a resin capable of radical polymerization is impregnated into pores of the vitrified bonded grinding wheel. 
   
   
       6 : The vitrified bonded grinding wheel according to  claim 5 , wherein the resin capable of radical polymerization consists of a resin which has a hardness in the range of 60-85, as measured by a type-D Shore hardness test. 
   
   
       7 : The vitrified bonded grinding wheel according to  claim 5 , wherein the resin capable of radical polymerization consists of a resin having a thermosetting property which is in a liquid state at a normal temperature, said resin selected from unsaturated polyester, vinyl ester and allyl ester. 
   
   
       8 : The vitrified bonded grinding wheel according to  claim 7 , wherein the resin capable of radical polymerization consists of a resin which has a hardness in the range of 60-85, as measured by a type-D Shore hardness test. 
   
   
       9 : The vitrified bonded grinding wheel according to  claim 8 , wherein the grinding wheel is constructed of a grinding wheel core and a ring-like grinding wheel substance adhered to either an outer circumference or an end surface of said grinding wheel core. 
   
   
       10 : The vitrified bonded grinding wheel according to  claim 9 , wherein the grinding wheel substance comprises a two-layer structure in which an abrasive grain layer having the superabrasive grains bonded with the vitrified bond is piled up on and bonded bodily to a foundation layer which does not include superabrasive grains. 
   
   
       11 : The vitrified bonded grinding wheel according to  claim 10 , wherein the grinding wheel substance comprises a plurality of segmental grinding wheel substances arranged on the outer circumference of the grinding wheel core in an annular fashion. 
   
   
       12 : A production process for a vitrified bonded grinding wheel comprising superabrasive grains selected from CBN and diamond bonded with a vitrified bond, wherein the process comprises the steps of filling a mold with a material comprising a mixture of abrasive grains and bonding agent; forming a grinding wheel substance through press-forming and burning operations; immersing the grinding wheel substance while in a vacuum, in a fluid resin capable of radical polymerization, to remove bubbles and to impregnate the resin capable of radical polymerization into the pores of the grinding wheel substance; and after setting of the resin, adhering the resin impregnated grinding wheel substance to a grinding wheel core. 
   
   
       13 : A production process for a vitrified bonded grinding wheel comprising superabrasive grains selected from CBN and diamond bonded with a vitrified bond, wherein the process comprises the steps of filling at least one mold with a material comprising a mixture of abrasive grains and bonding agent; forming a plurality of segmental grinding wheel substances through press-forming and burning operations; immersing the segmental grinding wheel substances while in a vacuum, in a fluid resin capable of radical polymerization, to remove bubbles and to impregnate the resin capable of radical polymerization into the pores of the segmental grinding wheel substances; and after setting of the resin, adhering the resin impregnated segmental grinding wheel substances to an outer circumference of a grinding wheel core.