Glossary for Abrasive Grains

• Abrasive Grains

  The individual grits of abrasive mineral, also called grit, or abrasive mineral.

• Bulk Density

  Sometimes referred to as "density" or "loose packed density" (LPD). Weight (grams) per volume (cubic centimeters) of loose packed abrasive grain. Generally indicative of the grain shape.

• Chemical Composition

  A chemical analysis of an abrasive.

• Coarse

  Composed of comparatively large particles.

• Coarse Grading

  Abrasive grain with too many large particles. A sieve analysis with too much material retained on the largest opening sieves in the specification.

• Coarse Grits

  Generally particles extremely large for the abrasive grain size.

• Fine

  Composed of comparatively small particles.

• Fine Grading

  Abrasive grain with too many small particles as specified on a sieve analysis.

• Grade

  Definition of size of abrasive grain.

• Grain Size

  The nominal size of the abrasive particle expressed in grit number, e.g., 50 grit.

• Grit

  Similar to grade.

• Macrogrits

  Generally abrasive grain sizes coarser than 240 or 280 grits.

• Mesh

  Generally interwoven wire screening used to sift or test abrasive grain. Sometimes wrongly used to describe abrasive grain size.

• Microgrits

  Generally abrasive grain sizes finer than 220 or 240 grits.

• Micro Inch

  A unit of measure of length equal to one millionth of an inch, smaller than a micron since one inch is approximately 1/39th of a meter.

• Micron

  One millionth of a meter. Generally used to define average particles size of microgrits (powders).

• Mixed Grits

  Generally a condition where two grit sizes are unintentionally mixed together.

• Particle Size

  Average diameter of an abrasive grain.

• Screen

  1) A sieve.
  2) A machine with screening surface(s) used to classify materials by size.

• Screen Sizes

  Another term for macrogrits.

• Sedimentation Sizes

  Another term for microgrits.

• Sedimentometer

  A device for measuring particle size distribution using the time it takes a sample of material to settle a given distance, using Stokes Law.

• Sieve

  Generally, interwoven mesh mounted on a frame and used for testing or sifting abrasive grain.

• Sieve Sizes

  Another term for macrogrits.

• Test Sieve

  A specially manufactured sieve used for testing particle size.

• Toughness

  Resistance to abrading of abrasive grain.

• Viscosity

  Resistance to abrading of abrasive grain.