Resinoid grinding wheels containing nickel-coated cubic boron nitride particles

Abstract

An improved resinoid grinding wheel particularly useful for the wet or dry grinding of hardened steels and steel alloys utilizes nickel-coated cubic boron nitride particles as the abrasive medium.

What we claim as new and desire to secure by Letters Patent of the United States is: 
     
       1. In a grinding wheel for hardened steel and steel alloys, an abrasive surface consisting of nickel-coated cubic boron nitride particles, the nickel constituting from 30 to 80 weight percent of the coated particles, said coated particles being embedded in a matrix of resinous material selected from the group consisting of phenol-formaldehyde, urea-formaldehyde, melamine-formaldehyde, epoxy, polyester, polyamide and polyimide resins, and mixtures thereof.Iadd., said wheel being formed in a mold by pressing to a stop.Iaddend.. 
     
     
       2. A grinding wheel as claimed in claim 1 wherein the resinous material is phenol formaldehyde. 
     
     
       3. A grinding wheel as claimed in claim 1 wherein the resinous material is a polyimide. 
     
     
       4. A method of making an abrasive wheel for hardened steel and steel alloys comprising applying a coating of nickel to a quantity of cubic boron nitride particles, the nickel constituting about 30 to 80 weight percent of the coated particles, mixing said coated particles with resinous material, selected from the group consisting of phenol-formaldehyde, urea-formaldehyde, melamine-formaldehyde, epoxy, polyester, polyamide and polyimide resins, and mixtures thereof and forming the coated cubic boron nitride resinous material mixture as the abrasive surface of a grinding wheel .Iadd.in a mold by pressing to a stop.Iaddend.. 
     
     
       5. A .Iadd.method of making an abrasive .Iaddend.grinding wheel as claimed in claim 4 wherein the resinous material is phenol formaldehyde. 
     
     
       6. A .Iadd.method of making an abrasive .Iaddend.grinding wheel as claimed in claim 4 wherein the resinous material is a polyimide .Iadd.and said pressing to a stop step is carried out at 5000 p.s.i..Iaddend.. .Iadd.7. A method of grinding hardened steel and steel alloys comprising the steps of: providing an abrasive grinding wheel whose surface comprises nickel-coated cubic boron nitride particles, the nickel constituting about 30 to 80 weight percent of the coated particle, in a matrix of resinous material selected from the group consisting of phenol-formaldehyde, urea-formaldehyde, melamine-formaldehyde, epoxy, polyester, polyamide and polyimide resins, and mixtures thereof, said wheel being formed in a mold by pressing to a stop; providing a hardened steel or steel alloy workpiece; rotating said grinding wheel; and contacting said workpiece with said rotating abrasive surface, whereby said surface abrades said workpiece..Iaddend. .Iadd.8. The method of claim 7, wherein said resinous material is phenol formaldehyde..Iaddend. .Iadd.9. The method of claim 7, wherein said resinous material is a polyimide..Iaddend.