Drilling or abrading tool having a working surface with an array of blind apertures plugged with super-abrasive material

Abstract

A drill bit includes a crown portion that has a plurality of blades that are separated from each other by a junk slot. Each blade includes a plurality of blind micro-holes formed in a working surface of the blade where each blind micro-hole in the plurality of blind micro-holes has a depth of 2 mm to 10 mm and a circular cross-section with a diameter of 1 mm to 3.5 mm. A super-abrasive material fills each blind micro-hole of the plurality of blind micro-holes. The super-abrasive material filling each of the plurality of blind apertures may be a polycrystalline diamond compact or an impregnated diamond material (such as formed by fused tungsten carbide impregnating randomly distributed diamond particles). The blind apertures may be formed in the working surface using electrical discharge machining

What is claimed is: 
     
         1 . A drill bit, comprising:
 a crown portion comprising a plurality of blades separated from each other by a junk slot, each blade comprising:
 a plurality of blind micro-holes formed in a working surface of the blade, wherein each blind micro-hole in the plurality of blind micro-holes has a depth of 2 mm to 10 mm and a circular cross-section with a diameter of 1 mm to 3.5 mm; and 
 a super-abrasive material filling each blind micro-hole of the plurality of blind micro-holes. 
   
     
     
         2 . The drill bit of  claim 1 , wherein the filled blind micro-holes cover over half of the working surface of each blade. 
     
     
         3 . The drill bit of  claim 2 , wherein the filled blind micro-holes cover substantially the entire working surface of each blade. 
     
     
         4 . The drill bit of  claim 1 , wherein each blind micro-hole in the plurality of blind micro-holes has an aspect ratio in a range of 2:1 to 5:1. 
     
     
         5 . The drill bit of  claim 1 , wherein the blind micro-holes are separated from each other by a distance in a range of two times the diameter to four times the diameter. 
     
     
         6 . The drill bit of  claim 1 , wherein the super-abrasive material includes super-abrasive particles selected from the group consisting of: diamond particles, thermally stable polycrystalline diamond particles, and cubic boron nitride particles. 
     
     
         7 . The drill bit of  claim 1 , wherein the plurality of blind micro-holes formed in said working surface of each blade are arranged in a regular and repeating pattern. 
     
     
         8 . The drill bit of  claim 7 , wherein the plurality of blind micro-holes formed in said working surface of each blade are arranged in an array having a matrix format with at least 5 columns and at least 5 rows. 
     
     
         9 . The drill bit of  claim 8 , wherein the plurality of blind micro-holes formed in said working surface of each blade are arranged in an array having a matrix format with at least 10 columns and at least 10 rows. 
     
     
         10 . The drill bit of  claim 1 , wherein each blade is made of hardened steel. 
     
     
         11 . The drill bit of  claim 1 , wherein each blade is made of tungsten carbide. 
     
     
         12 . The drill bit of  claim 1 , wherein the super-abrasive material filling each of the plurality of blind micro-holes comprises a polycrystalline diamond compact. 
     
     
         13 . The drill bit of  claim 1 , wherein the super-abrasive material filling each of the plurality of blind micro-holes comprises an impregnated diamond material. 
     
     
         14 . The drill bit of  claim 13 , wherein impregnated diamond material comprises fused tungsten carbide impregnating randomly distributed diamond particles. 
     
     
         15 . The drill bit of  claim 1 , wherein each blade comprises a plurality of tool segments attached to an outer surface of a bit body, each tool segment comprising the filled blind micro-holes. 
     
     
         16 . The drill bit of  claim 1 , wherein the blind micro-holes formed in said working surface of each blade comprise electrical discharge machined micro-holes. 
     
     
         17 . The drill bit of  claim 1 , wherein the blind micro-holes formed in said working surface of each blade are oriented perpendicular to said working surface of each blade. 
     
     
         18 . The drill bit of  claim 1 , wherein the blind micro-holes formed in said working surface of each blade are oriented non-perpendicular to said working surface of each blade. 
     
     
         19 . The drill bit of  claim 18 , wherein the orientation of the blind micro-holes formed in said working surface of each blade varies along a length of each blade. 
     
     
         20 . The drill bit of  claim 1 , wherein the super-abrasive material filling each of the plurality of blind micro-holes exhibits a variation in characteristic as a function of the depth, wherein the variation in characteristic is selected from a group of characteristics consisting of diamond distribution, diamond content, and powder matrix component distribution. 
     
     
         21 . A drill bit, comprising:
 a crown portion comprising a plurality of blades separated from each other by a junk slot, each blade comprising:
 a plurality of blind apertures formed in a working surface of the blade, wherein each blind aperture in the plurality of blind apertures has a depth of 2 mm to 10 mm and a rectangular cross-section having a width of 1 mm to 4 mm and a length of 5 mm to 15 mm; and 
 a super-abrasive material filling each blind aperture of the plurality of blind apertures. 
   
     
     
         22 . The drill bit of  claim 21 , wherein the super-abrasive material includes super-abrasive particles selected from the group consisting of: diamond particles, thermally stable polycrystalline diamond particles, and cubic boron nitride particles. 
     
     
         23 . The drill bit of  claim 21 , wherein the filled blind apertures cover substantially the entire working surface of each blade. 
     
     
         24 . The drill bit of  claim 21 , wherein the plurality of blind apertures formed in said working surface of each blade are arranged in an array having a matrix format with at least 5 columns and at least 5 rows. 
     
     
         25 . The drill bit of  claim 21 , wherein the blind apertures formed in said working surface of each blade comprise electrical discharge machined apertures.