Bonded abrasive articles and methods of manufacture

Abstract

Methods for manufacturing bonded abrasive articles, for example vitrified bonded grinding wheels. A bondable abrasive composition is prepared including abrasive particles, a binder medium and a gamma-pyrone pore inducing material, such as ethyl maltol. A precursor abrasive structure is formed from the composition. The gamma-pyrone pore inducing material is removed from the precursor abrasive structure to provide a porous precursor abrasive structure that is further processed to provide a bonded abrasive article. In some embodiments, the binder medium includes a vitreous bonding material, and the bonded abrasive article is a porous vitrified bonded grinding wheel.

What is claimed is: 
     
         1 . A method for manufacturing a bonded abrasive article, the method comprising:
 preparing a bondable abrasive composition, the bondable abrasive composition comprising a plurality of abrasive particles, a binder, and a pore inducing material;   forming a precursor abrasive structure with the bondable abrasive composition, wherein forming comprises molding the bondable abrasive composition;   removing the pore inducing material, wherein removing comprises heating the precursor abrasive structure above a sublimation point of the pore-inducing material; and   processing the porous precursor abrasive structure into the bonded abrasive article.   
     
     
         2 . The method of  claim 1 , wherein the pore-inducing polymer is free of naphthalene. 
     
     
         3 . The method of  claim 1 , wherein the pore-inducing polymer is environmentally benign. 
     
     
         4 . The method of  claim 1 , wherein the pore-inducing polymer is a heterocyclic compound. 
     
     
         5 . The method of  claim 1 , wherein the pore-inducing polymer is nonreactive with respect to the abrasive particles. 
     
     
         6 . The method of  claim 5 , wherein the pore-inducing polymer is nonreactive with respect to the binder. 
     
     
         7 . The method of  claim 1 , wherein the pore-inducing polymer experiences substantially no volume change during the step of forming the precursor abrasive structure. 
     
     
         8 . The method of  claim 7 , wherein forming the precursor abrasive structure comprises compressing the bondable abrasive composition. 
     
     
         9 . The method of  claim 8 , wherein compressing comprises a pressure less than 400kg/cm 3 . 
     
     
         10 . The method of  claim 1 , wherein the pore-inducing polymer is substantially insoluble in water. 
     
     
         11 . The method of  claim 1 , wherein removing the pore inducing material comprises heating to a first temperature, wherein processing the porous precursor abrasive structure comprises heating to a second temperature, and wherein the first temperature is less than the second temperature. 
     
     
         12 . The method of  claim 11 , wherein the first temperature is between about 140° C. and about 175° C. 
     
     
         13 . A bondable abrasive composition comprising:
 a plurality of abrasive particles;   a binder configured to bind the plurality of abrasive particles into a bonded abrasive article; and   a pore-inducing material configured to create pores within the bonded abrasive article, wherein the pore-inducing material is an environmentally benign material configured to sublimate during processing of the bonded abrasive composition.   
     
     
         14 . The bondable abrasive composition of  claim 13 , wherein the pore-inducing material is configured to sublimate at a temperature between about 140° C. and about 175° C. 
     
     
         15 . The bondable abrasive composition of  claim 13 , wherein the pore-inducing polymer is environmentally benign. 
     
     
         16 . The bondable abrasive composition of  claim 13 , wherein the pore-inducing polymer is a heterocyclic compound. 
     
     
         17 . The bondable abrasive composition of  claim 13 , wherein the pore-inducing polymer is nonreactive with respect to the abrasive particles and the binder. 
     
     
         18 . The bondable abrasive composition of  claim 13 , wherein the pore-inducing polymer experiences substantially no volume change under pressures up to 400kg/cm 3 . 
     
     
         19 . The bondable abrasive composition of  claim 13 , wherein the abrasive particles comprise agglomerates. 
     
     
         20 . The bondable abrasive composition of  claim 13 , wherein the abrasive particles comprise shaped abrasive particles or crushed particulates.