Abrasive article with abrasive particles having random rotational orientation within a range

Abstract

An abrasive article includes a plurality of abrasive particles and the rotational orientation of at least a portion of the abrasive particles about the z-axis varies randomly within a defined range, and the spacing of the abrasive particles along the y-axis varies randomly.

What is claimed is: 
     
         1 . An abrasive article having a y-axis, an x-axis transverse to the y-axis, and a z-axis orthogonal to the y-axis and x-axis, the abrasive article comprising a plurality of abrasive particles, wherein the rotational orientation of at least a portion of the abrasive particles about the z-axis varies randomly within a defined range, and wherein the spacing of the abrasive particles varies randomly along the y-axis. 
     
     
         2 . An abrasive article as defined in  claim 1 , wherein the spacing of the abrasive particles in the x-axis direction is random. 
     
     
         3 . An abrasive article as defined in  claim 2 , wherein the spacing of the abrasive particles is more uniform in the x-axis direction than the y-axis direction. 
     
     
         4 . An abrasive article as defined in  claim 3 , wherein the spacing of the abrasive particles in the x-axis direction varies within a defined range. 
     
     
         5 . An abrasive article as defined in  claim 4 , wherein the abrasive particles are arranged in rows, and further wherein the average deviation of the location of an abrasive particle within a row varies randomly by no more than about plus or minus (+/−) 4 times the thickness of the abrasive particle. 
     
     
         6 . An abrasive article as defined in  claim 1 , wherein at least a portion of the abrasive particles are arranged in a row having a longitudinal axis, each abrasive particle has a longitudinal axis, and the longitudinal axis of at least a portion of the abrasive particles is within a defined range relative to the longitudinal axis of the row. 
     
     
         7 . An abrasive article as defined in  claim 6 , wherein the longitudinal axis of the row is generally parallel to the first axis of the abrasive article y-axis. 
     
     
         8 . An abrasive article as defined in  claim 6 , wherein the longitudinal axis of the row is offset at an angle from the abrasive article y-axis. 
     
     
         9 . An abrasive article as defined in  claim 1 , wherein the abrasive particles are provided in a generally arcuate path and the y-axis is tangent to the arcuate path. 
     
     
         10 . An abrasive article as defined in  claim 1 , wherein the z-direction rotational orientation of at least about 55 percent of the abrasive particles is within about +/−45 degrees of the average particle z-direction rotational orientation. 
     
     
         11 . An abrasive article as defined in  claim 1 , wherein at least a portion of the abrasive particles are elongate and are configured to be oriented in an upright position by passing them through an elongate slot. 
     
     
         12 . An abrasive article as defined in  claim 1 , wherein at least a portion of the abrasive particles have a length, width, thickness and an elongate edge, and further wherein width and length are greater than the thickness. 
     
     
         13 . An abrasive article as defined in  claim 1 , wherein at least a portion of the abrasive particles have a generally plate-like shape. 
     
     
         14 . An abrasive article as defined in  claim 1 , wherein at least a portion of the abrasive particles comprise crushed abrasive particles, shaped abrasive particles, and combinations thereof. 
     
     
         15 . An abrasive article as defined in  claim 1 , wherein the abrasive particles comprise an agglomerate having a plate-like shape. 
     
     
         16 . An abrasive article as defined in  claim 1 , wherein the abrasive article includes a mixture of abrasive particles comprising a first portion having a generally uniform size and shape, and a second portion having a generally uniform size and a non-uniform shape. 
     
     
         17 . An abrasive article as defined in  claim 1 , wherein about 80-90 percent of the abrasive particles are inclined at an angle of at least about 45 degrees from the plane defined by the x and y axes. 
     
     
         18 . A coated abrasive article comprising:
 a) a backing having opposed first and second major surfaces, a longitudinal axis and a transverse axis;   b) a make coat on at least a portion of one of the first and second major surfaces; and   c) a plurality of abrasive particles secured to the backing via the make coat, wherein each abrasive particle includes a y-direction axis extending in the direction of the longitudinal axis of the backing, and a z-direction axis orthogonal to the longitudinal axis of the backing;   wherein the rotational orientation of a majority of the abrasive particles about the z-axis varies randomly within a defined range, and further wherein the spacing of the abrasive particles in the y-direction varies randomly.   
     
     
         19 . An abrasive disc comprising:
 a) a backing having opposed first and second major surfaces, an annular path, and a z-axis orthogonal to at least one of the first and second major surfaces;   b) a make coat on at least one of the first and second major surfaces; and   c) a plurality of abrasive particles secured to the backing via the make coat, wherein the rotational orientation of a majority of the abrasive particles about the second axis varies randomly within a defined range, and further wherein the spacing of the abrasive particles along the annular path varies randomly.   
     
     
         20 . A method of grinding metal, comprising the steps of providing an abrasive article as defined in  claim 18  in the form of a continuous belt, and bringing the abrasive belt into contact with the metal.