Process for preparing a resin-bonded grinding article containing stress-absorbing particulate material

Claim 2

The process of claim 1 further characterized in that the particulate solid spacer material is a curable organic resin powder.

Claim 3

The process of claim 1 further characterized in that the liquid binding resin is a liquid-epoxy resin and the particulate solid-spacer material is a curable organic resin powder.

Claim 4

The process of claim 4 further characterized in that the liquid epoxy resin cures at temperatures lower than the resin powder.

Claim 5

The process of claim 1 further characterized in that the particulate solid-spacer material is an inorganic particulate material.

Claim 6

The process of claim 1 further characterized in that the grinding article is a grinding wheel or segment thereof wherein the particulate solid-spacer material is an epoxy-resin powder and the liquid-binding resin is a curable liquid epoxy resin.

Claim 7

The process of claim 7 further characterized in that the curable liquid epoxy resin gels at temperatures below the curing temperatures of the epoxy resin powder.

Claim 8

The process of claim 7 further characterized in that the abrasive mixture is heated in the mold to temperatures sufficient to gel and initiate the cure of the liquid epoxy resin and thereafter heated at elevated temperatures to complete the cure of the epoxy resin powder.

Claim 9

The process of preparing the rigid grinding article of claim 1 further characterized in that the abrasive particles constitute from about 30 to 50 percent by volume of the grinding article.

Claim 10

The process of claim 7 further characterized in that the total amount of liquid binding resin and the solid spacer resin powder constitute from about 35 to 45 percent by volume of the grinding wheel.

Claim 11

The process of claim 6 further characterized in that the solid spacer is an inorganic particulate material selected from the class consisting of glass beads, mica, graphite powder and iron pyrite.

Claim 12

The process of claim 1 further characterized in that the particulate solid spacer material is selected from the class consisting of polyethylene powder, polystyrene powder, epoxy powders, phenolic powders, silicone resin powders, glass beads, mica, graphite powder and iron pyrite and the curable liquid-binding resin is selected from the class consisting of epoxy resins, polyethylene, polystyrene, phenolic resins and silicone resins.

Claim 13

The process of claim 13 further characterized in that the abrasive particles are selected from the class consisting of fused alumina, sintered alumina, silicone carbide, emery, garnet, talc and pumice.

Claim 14

A process for preparing a resin-bonded rigid grinding article containing above about 75 percent by weight thereof of abrasive particles wherein said particles are spaced apart in the article by solid-spacer material which comprises a. preparing an abrasive mixture consisting essentially of i. a sufficient amount of abrasive particles to provide an abrasive content in the mixture of from about 75 to about 100 percent of the bulk density of the abrasive; said abrasive having a particle size of frOm about 600 to 10 mesh, ii. from about 5 to 30 percent by weight of the abrasive particles of stress-absorbing particulate solid-spacer material selected from the class consisting of polyethylene powder, polystyrene powder, epoxy powders, phenolic powders, silicone resin powders, glass beads, mica, graphite powder and iron pyrite, iii. and from about 10 to 35 percent by weight of the abrasive particles of a liquid-binding resin capable of being cured to a solid without a substantial change in volume; said liquid-binding resin selected from the class consisting of epoxy resins, polyethylene, polystyrene, phenolic resins and silicone resins, b. filling the mold with the abrasive mixture without substantially compressing said mixture, and c. curing by heating the abrasive mixture in the mold in the absence of a significant amount of external pressure to form a rigid grinding article having the shape and volume substantially as that of the mold.