Apertured Abrasive Disk Assembly With Improved Flow Dynamics

Abstract

The evacuation properties of an abrasive disk are improved by forming its apertures to exhibit a configuration that will direct process fluids onto or away from a workpiece (or contact) interface through capillary action, surface tension/affinity, and/or boundary layer pump actions. The capillary action is accomplished by modifying the geometries of the apertures to form capillary tubes, where the orientation and lift angle of the capillary tubes is controlled to improve the flow of relatively thin layers of liquids. The surface tension/affinity between a liquid material and the abrasive disk is controlled by modifying the through-hole apertures to exhibit a serrated inner surface, which will decrease the attraction between the material of the abrasive disk and the process liquid. A plurality of apertured disks may be stacked, and their respective apertures properly arranged on each surface, to create a Tesla pump such that the kinetic energy associated with rotation of the disk assembly will preferentially bias both the vertical and tangential flow of liquids between the working surface and the disk assembly.

1 . An abrasive disk assembly comprising:
 a substrate having a top surface and a bottom surface, at least the bottom surface having a coating of an abrasive composition; and   a plurality of apertures formed through the thickness of the substrate wherein the plurality of apertures are configured to bias the flow of process fluids therethrough.   
     
     
         2 . An abrasive disk assembly as defined in claim I wherein the plurality of apertures are configured as capillary tubes to bias the flow of liquids therethrough. 
     
     
         3 . An abrasive disk assembly as defined in  claim 2  wherein the plurality of capillary tube apertures comprise essentially identical dimensions and orientation. 
     
     
         4 . An abrasive disk assembly as defined in  claim 2  wherein at least a first group of the capillary tube apertures are oriented to direct fluid away from a surface being worked and a second group of the capillary tube apertures are oriented to direct fluid toward a surface being worked. 
     
     
         5 . An abrasive disk assembly as defined in  claim 2  wherein the plurality of capillary tube apertures comprise a teardrop-shaped configuration. 
     
     
         6 . An abrasive disk assembly as defined in  claim 5  wherein each teardrop-shaped aperture is defined by an internal angle φ that is defined by the relation 2(90°-α), where α is defined as the wetting angle of the fluid passing through the aperture. 
     
     
         7 . An abrasive disk assembly as defined in  claim 2  wherein the plurality of capillary tube apertures comprise apertures of varying dimension. 
     
     
         8 . An abrasive disk assembly as defined in  claim 2  wherein the plurality of capillary tube apertures are disposed at a predetermined angle with respect to the thickness of the substrate. 
     
     
         9 . An abrasive disk assembly as defined in  claim 1  wherein the plurality of apertures comprise a serrated interior wall to reduce the affinity between the material forming the substrate and the liquid passing therethrough. 
     
     
         10 . An abrasive disk assembly as defined in  claim 1  wherein the assembly further comprises
 a plurality of apertured disks aligned with the substrate in a stacked configuration so as to create boundary layers therebetween, wherein upon rotation of the abrasive disk assembly the combination of the apertures and boundary layers create laminar flow of liquids between the assembly and a worked surface.