Abrasive Grain / Grit / Powder, Inorganic:

Description:

Abrasives are substances both natural and synthetic that are used to grind, polish, abrade, scour, clean, or otherwise remove solid material usually by rubbing action (as in a grinding wheel), but also by impact (pressure blasting). The most important physical properties of materials that qualify as abrasives are hardness, toughness (or rigidity), grain shape and size, the character of fracture (or cleavage), and purity (or uniformity). In the final analysis, the choice of a high-grade abrasive depends upon the quality and quantity of work performed by the abrasive per unit of cost. The initial cost of an artificial abrasive may be much greater than that of a natural abrasive, but the artificial mineral may do so much better work and do it so much faster that the ultimate cost is less. It is for this reason that artificial abrasives have largely replaced natural abrasives.

Manufactured (Artificial) Abrasives Available:

Aluminum oxide (fused), barium titanate, boron carbide, boron nitride, burundum, calcium carbonate, calcium phosphate, cerium oxide, chromium oxide, clay (hard burned), diamond, glass, iron oxide, lamp black, lime, magnesia, manganese dioxide, mullite, periclase, silicon carbide (fused), sintered abrasives, sol-gel abrasives, steel shot, steel grit (angular), tantalum carbide, tin oxide, titanium carbide, tungsten carbide, wheat starch, zirconium oxide (un-stabilized), zirconium oxide (stabilized) and zirconium silicate. And many more!

Natural Abrasives Available (Listed In Approximate Order By Mohs Hardness Scale):

Natural diamond, corundum, emery, garnet, staurolite, flint, novaculite, quartz, quartzite, sandstone, limestone, basalt, feldspar, granite, mica, perlite, pumice, apatite, calcite, chalk, clay, diatomite, dolomite, iron oxides, limestone, and talc.

Surface Improvement Technology:

As it is applied to metal removal, has grown substantially in the past few years. Tighter tolerances, new workpiece materials, and new and improved abrasives are the main reasons for this growth. This type of surface finishing (metal removal) has several names describing very different processes. However, they all have one common function; all are low-velocity abrading processes using lower cutting speeds (compared to grinding) and lower pressure to minimize heat, resulting in an excellent surface, size, and geometry control.

  • Polishing is the use of abrasives to create a smoother surface with little, if any; geometry improvements (seal areas, low loading-bearing areas).
  • Lapping is the process of folding the workpiece material. It incorporates a loose abrasive for a very fine surface finish and small amounts of stock removal. (Generally used on flat applications)
  • Honing is generally associated with inside diameter surface finishing. It uses abrasives to improve surface finish and geometry characteristics such as roundness, taper, and sizing. (High wear areas and applications needing close tolerances.)
  • Superfinishing generally incorporates vitrified abrasive products such as diamond and CBN. It applies a light pressure with a high reciprocating action to achieve improved surface finish and geometry characteristics (outside diameter applications with high load areas and tight tolerances).
  • Micro-finishing has grown significantly in the past few years. Generally associated with abrasive tape as the media, it has replaced most polishing applications where high loads and tight tolerances are required.
  • Other surface finishing methods such as brushing and buffing improve the workpiece appearance and sometimes are incorporated into other processes to enhance results. These processes have deviations within their category which allow varying process results.

Synonyms:

Aluminum oxide (fused), barium titanate, boron carbide, boron nitride, burundum, calcium carbonate, calcium phosphate, cerium oxide, chromium oxide, clay (hard burned), diamond, glass, iron oxide, lamp black, lime, magnesia, manganese dioxide, mullite, periclase, silicon carbide (fused), sintered abrasives, sol-gel abrasives, steel shot, steel grit (angular), tantalum carbide, tin oxide, titanium carbide, tungsten carbide, wheat starch, zirconium oxide (unstabilized), zirconium oxide (stabilized), zirconium silicate, natural diamond, corundum, emery, garnet, staurolite, flint, novaculite, quartz, quartzite, sandstone, limestone, basalt, feldspar, granite, mica, perlite, pumice, apatite, calcite, chalk, clay, diatomite, dolomite, iron oxides, limestone, talc.

Chemical Properties:

Purities are available from PEPL as high of a typical purity as 99.999% down to low purity recycled abrasive grains or powders

Physical Properties:

Numerous shape and size options are usually readily available from PEPL as large as 50 mm grinding and tumbling media down to as small as 20 – 100-nanometer particles.

Typical Applications:

Buffing, coated abrasives, coatings, deburring, electrical potting insulation, fillers, fining, flow finishing, friction, grinding wheels, a heat transfer component, investment casting molds, wear resistant parts, metal lapping, polishing, pressure blasting, slurry sawing, tumbling, ultrasonic machining

Specifications:

Urethane Hardness NBS AbrasionTaber Abrasion
Durometer Shore ADurometer Shore DASTM D-394 Method BASTM D-1044
58 2587
75 600
80 110
85 125
90 17579
9548275118
 58370
 75250373