Conglomerate abrasive particles, abrasive articles including the same, and methods of making the same

Abstract

A method of making conglomerate abrasive particles includes: providing agglomerate abrasive particles comprising mineral particles in a first vitreous binder; combining the agglomerate abrasive particles with a second vitreous binder material precursor to form precursor conglomerate abrasive particles; and heating the precursor conglomerate abrasive particles to convert the second vitreous binder material precursor into a second vitreous binder, different from the first vitreous binder, thereby forming the conglomerate abrasive particles. The first vitreous binder differs from the second vitreous binder by at least one of: i) elemental composition, or ii) an intrinsic physical property; and wherein the conglomerate abrasive particles can pass through a testing sieve having one-millimeter openings. Conglomerate abrasive particles preparable by the method, and abrasive articles containing them, are also disclosed.

What is claimed is: 
     
         1 . Conglomerate abrasive particles comprising agglomerate abrasive particles, the agglomerate abrasive particles comprising mineral particles and a first vitreous binder, wherein the agglomerate abrasive particles are bonded together by a second vitreous binder, and wherein the first vitreous binder differs from the second vitreous binder by at least one of:
 i) elemental composition, or   ii) an intrinsic physical property, and   wherein the conglomerate abrasive particles are sized according to an abrasives industry recognized specified nominal grade, and   wherein the conglomerate abrasive particles can pass through a testing sieve having 1-millimeter openings and conforming to test method ASTM E-1113.   
     
     
         2 . Conglomerate abrasive particles according to  claim 1 , wherein the first vitreous binder and the second vitreous binder have the same elemental composition. 
     
     
         3 . Conglomerate abrasive particles according to  claim 1 , wherein the first vitreous binder and the second vitreous binder have different elemental compositions. 
     
     
         4 . Conglomerate abrasive particles according to  claim 1 , wherein the mineral particles comprise diamond particles. 
     
     
         5 . Conglomerate abrasive particles according to  claim 4 , wherein the diamond particles have a median size of 0.1 to 15 microns, and the agglomerate abrasive particles median size is from 40 to 400 microns, inclusive. 
     
     
         6 . Conglomerate abrasive particles according to  claim 1 , wherein the second vitreous binder is less friable than the first vitreous binder. 
     
     
         7 . Conglomerate abrasive particles according to  claim 1 , wherein the median size of the conglomerate abrasive particles is at least 2.5 times greater than the median size of the agglomerate abrasive particles. 
     
     
         8 . An abrasive article comprising conglomerate abrasive particles retained in a binder material, wherein the conglomerate abrasive particles comprise agglomerate abrasive particles, the agglomerate abrasive particles comprising mineral particles and a first vitreous binder, wherein the agglomerate abrasive particles are bonded together by a second vitreous binder, and wherein the first vitreous binder differs from the second vitreous binder by at least one of:
 i) elemental composition, or   ii) an intrinsic physical property, and   wherein the conglomerate abrasive particles are sized according to an abrasives industry recognized specified nominal grade, and   wherein the conglomerate abrasive particles can pass through a testing sieve having 1-millimeter openings and conforming to test method ASTM E-1113.   
     
     
         9 . The abrasive article of  claim 8 , wherein the abrasive article comprises a structured abrasive article comprising an abrasive layer secured to a major surface of a backing, wherein the abrasive layer comprises shaped abrasive composites, and wherein at least some of the shaped abrasive composites comprise the conglomerate abrasive particles retained in the binder material. 
     
     
         10 . An abrasive article according to  claim 8 , wherein the abrasive layer has a bearing area ratio between about 20 percent to about 70 percent. 
     
     
         11 . An abrasive article according to  claim 8 , wherein the mineral particles comprise diamond particles. 
     
     
         12 . An abrasive article according to  claim 8 , wherein the diamond particles have a median size of 0.1 to 15 microns, and the agglomerate abrasive particles median size is from 40 to 400 microns, inclusive.