Grinding Wheel Materials 210

This class describes common abrasive and bond materials for grinding wheels, as well as their applications.

Class Details

Class Name:
Grinding Wheel Materials 210
This class describes common abrasive and bond materials for grinding wheels, as well as their applications.
Number of Lessons:
Additional Language:
Related 2.0 Class:
Grinding Wheel Materials 331

Class Outline

  • Objectives
  • Material Variety
  • Abrasive Grain Characteristics
  • Abrasive Grain Classifications
  • Aluminum Oxide
  • Zirconia Alumina
  • Silicon Carbide
  • Ceramic Aluminum Oxide
  • Diamond
  • Cubic Boron Nitride
  • Bond Characteristics
  • Wheel Grade
  • Bond Material Types
  • Vitrified Bonds
  • Organic Bonds
  • Superabrasive Bonds
  • Standard Wheel Markings
  • Superabrasive Wheel Markings
  • Summary


  • Understand the factors that affect grinding material selection.
  • List the most important characteristics of abrasive grains.
  • Cite different ways abrasive grains may be classified.
  • Describe the defining characteristics of aluminum oxide.
  • Describe the defining characteristics of zirconia alumina.
  • Describe the defining characteristics of silicon carbide.
  • Describe the defining characteristics of ceramic aluminum oxide.
  • Describe the defining characteristics of diamond.
  • Describe the defining characteristics of cubic boron nitride.
  • Describe the characteristics of bonds.
  • Explain what determines wheel grade.
  • Name the four types of wheel bonds.
  • Describe the defining characteristics of vitrified bonds.
  • Describe the defining characteristics of organic bonds.
  • Describe the characteristics of superabrasive bonds.
  • List the categories on the standard abrasive wheel marking chart.
  • List the categories on the superabrasive wheel marking chart.



Vocabulary Term Definition
alumina The natural form of aluminum oxide.
aluminum oxide An abrasive made by fusing bauxite, iron, and coke that is widely used to grind ferrous materials. The natural form is called corundum.
American National Standards Institute A private, non-profit organization that administers and coordinates voluntary standards and systems.
arc furnace A heating unit that uses electric arcs between carbon electrodes to melt steel and manufacture abrasives. Also called an electric arc furnace.
bauxite A form of aluminum oxide that contains several impurities.
bond The "glue" or adhesive material that holds abrasive grains together in a grinding wheel. Bonds may be vitrified, organic, metal, or electroplated.
carbide A compound developed by the combination of carbon with usually tungsten, titanium, or tantalum that is used in metal cutting tools for its hardness and wear resistance.
carbon steel The basic type of steel, which contains less than 3% of elements other than iron and carbon.
cast iron A metal consisting of iron, over 2.11% carbon, and 1 to 3% silicon. Cast irons will normally contain trace amounts of other elements.
ceramic aluminum oxide An exceptionally hard, strong, sharp abrasive made from a process in which alumina gel is dried and crushed. Ceramic aluminum oxide has the ability to refracture at the sub-micron level.
chemical vapor deposition A method of manufacturing diamonds that uses heat and radio waves or microwaves to break a carbon-rich gas into pieces that reassemble themselves into diamond.
coke The carbon-containing residue remaining from coal distillation.
conventional abrasive One of several inexpensive abrasives of varying hardnesses commonly used in industry for material removal.
cubic boron nitride The second-hardest substance after diamond. Cubic boron nitride (CBN) is manufactured in a high-heat, high-pressure sintering process.
diamond The hardest known substance. Made from carbon, diamond is both a naturally occurring and manufactured abrasive.
electroplated bond A superabrasive bond accomplished by immersing a metal wheel in an electrically charged chemical bath that contains metal particles.
ferrous metal A metal containing iron.
friability The ability of abrasive grains to fracture and self-sharpen under stress.
grade The strength of the bond in an abrasive wheel.
graphite A soft, black form of carbon. Graphite is used to manufacture diamonds.
hardness The ability of a material to resist penetration and scratching.
hexagonal boron nitride A boron-nitrogen compound that has a six-sided crystal structure.
high-speed steel A tool steel used to machine metals at high cutting speeds. High-speed steel stays hard at high temperatures and resists abrasion.
iron The fourth most abundant earth element. Iron is alloyed with carbon to make steel.
kiln An oven or furnace used for heating or drying.
lapping A precision abrasion process used to bring a surface to a desired state of finish or dimensional tolerance by removing an extremely small amount of material.
manufactured abrasive A material of extreme hardness created through chemical and/or physical processes that is used to shape other materials by a grinding or abrading action.
manufactured diamond The manufactured form of a carbon mineral that is the hardest substance known to man. It is manufactured through a high-heat, high-pressure process.
metal bond A bonding material used most often with superabrasive grinding wheels.
micron A measurement equal to one twenty-fifth of a thousandth of an inch (0.00004 inch).
natural abrasive A hard material found in the earth that is used to shape other materials by grinding or abrading. Sand and quartz are both natural abrasives.
natural diamond The mined form of a carbon mineral that is the hardest substance known to man.
nonferrous A material that does not contain iron. Aluminum, copper, and zinc are nonferrous metals.
organic bond An abrasive bonding material that contains carbon. Organic bonds tend to soften with heating.
porosity The relative number of openings or voids in a material.
porous Having many openings or voids.
post A structural beam that connects abrasive grains in a bonded abrasive grinding wheel.
resinoid bond An organic bond made of synthetic resin.
roll Long, cylindrical metal parts used in mills that make paper, sheet metal, and other similar products.
rubber bond An organic bond made of natural or synthetic rubber.
shellac bond An organic bond made of shellac, a material secreted on the bark of trees by an insect that has ingested tree sap.
silicon carbide A hard, brittle abrasive made by firing a mixture of quartz, petroleum coke, and small amounts of sawdust and salt in an electric furnace. Silicon carbide is known for its green color.
sintering The pressing and heating of powdered materials close to their melting point to create a solid shape. Sintering creates materials with very uniform contents.
steel A metal consisting of iron and carbon, usually with small amounts of manganese, phosphorus, sulfur, and silicon as well.
sub-micron A measurement less than one twenty-fifth of a thousandth of an inch (0.00004 inch).
superabrasive One of a group of relatively expensive but effective materials possessing superior hardness and abrasion resistance. Superabrasives include cubic boron nitride and diamond.
superalloy A metal alloy consisting of three or more elements that is very expensive and designed to exhibit high strength at elevated temperatures.
vitrified bond A clay-like abrasive bond that is generally hard and brittle.
void The space or pore between abrasive grains and posts on a bonded abrasive grinding wheel.
wrought iron A tough, malleable, and relatively soft form of iron containing less than 0.3 percent carbon.
zirconia alumina A type of tough, large-grain abrasive made from aluminum oxide and zirconium oxide. Often used in cutoff operations.
zirconium oxide A toxic, heavy, white powder used to manufacture zirconia alumina.