Abrasion (mechanical)
Encyclopedia
Abrasion is the process of scuffing, scratching, wearing down, marring, or rubbing away. It can be intentionally imposed in a controlled process using an abrasive. Abrasion can be an undesirable effect of exposure to normal use or exposure to the elements.

Types

Manufacturing processes often use abrasive
Abrasive
An abrasive is a material, often a mineral, that is used to shape or finish a workpiece through rubbing which leads to part of the workpiece being worn away...

s to remove material from a surface, to smooth the surface, to create controlled surface roughness, etc. Coated abrasive
Coated abrasive
A coated abrasive is an abrasive grain bonded to a flexible substrate using adhesives. Common substrates are paper, cloth, vulcanized fiber, and plastic films and come in grit sizes range from very coarse to ultrafine...

s, grinding wheel
Grinding wheel
A grinding wheel is an expendable wheel that is composed of an abrasive compound used for various grinding and abrasive machining operations...

s, sand blasting, and polishing are examples.

When things are used, abused, or subjected to the elements, abrasion may often occur.
For example:
  • Plastic lenses may scratch: Abrasion resistant coatings are available
  • Wind
    Wind
    Wind is the flow of gases on a large scale. On Earth, wind consists of the bulk movement of air. In outer space, solar wind is the movement of gases or charged particles from the sun through space, while planetary wind is the outgassing of light chemical elements from a planet's atmosphere into space...

     and particles it carries may scour and abrade outdoor sculptures
  • Sediment in moving water can abrade bridge footings
  • Glacier
    Glacier
    A glacier is a large persistent body of ice that forms where the accumulation of snow exceeds its ablation over many years, often centuries. At least 0.1 km² in area and 50 m thick, but often much larger, a glacier slowly deforms and flows due to stresses induced by its weight...

    s can abrade landscapes
  • Plastic kitchenware can be abraded by washing and scrubbing
  • Foot traffic can abrade ceramic floor tiles
  • Vibration
    Vibration
    Vibration refers to mechanical oscillations about an equilibrium point. The oscillations may be periodic such as the motion of a pendulum or random such as the movement of a tire on a gravel road.Vibration is occasionally "desirable"...

     can cause abrasion of printed paper label
    Label
    A label is a piece of paper, polymer, cloth, metal, or other material affixed to a container or article, on which is printed a legend, information concerning the product, addresses, etc. A label may also be printed directly on the container or article....

    s on packages
  • Use of knives on glass or metal cutting boards can abrade knife blades
  • Particles in the lubricant of an engine can abrade engine components
  • Scuffing can abrade clothing
  • Molded automotive parts can be abraded by contact with people and gravel

Abrasion in stone shaping

Ancient artists working in stone would use abrasion to create sculptures. The artist selected dense stones like carbonite and emory and rub them consistently against comparatively softer stones like limestone or granite. The artist would use different sizes and shapes of abrasives, or turn them in various ways as they rubbed, to create effects on the softer stone's surface. Water would be continuously poured over the surface to carry away particles. Abrasive technique in stone shaping was a long, tedious process that, with patience, resulted in eternal works of art in stone.

Abrasion resistance

The resistance of materials and structures to abrasion can be measured by a variety of test method
Test method
A test method is a definitive procedure that produces a test result.A test can be considered as technical operation that consists of determination of one or more characteristics of a given product, process or service according to a specified procedure. Often a test is part of an experiment.The test...

s. These often use a specified abrasive or other controlled means of abrasion. Under the conditions of the test, the results can be reported or can be compared items subjected to similar tests.

The use of proper lubricant
Lubricant
A lubricant is a substance introduced to reduce friction between moving surfaces. It may also have the function of transporting foreign particles and of distributing heat...

s can help control abrasion in some instances. Some items can be covered with an abrasion resistant material. Controlling the cause of abrasion is sometimes an option.

Standards

  • ASTM C448 Standard Test Methods for Abrasion Resistance of Porcelain Enamels
  • ASTM C944 Standard Test Method for Abrasion Resistance of Concrete or Mortar Surfaces by the Rotating-Cutter Method
  • ASTM C1027 Standard Test Method for Determining Visible Abrasion Resistance of Glazed Ceramic Tile
  • ASTM C1353 Standard Test Method for Abrasion Resistance of Dimension Stone Subjected to Foot Traffic Using a Rotary Platform, Double-Head Abraser
  • ASTM D968 Standard Test Methods for Abrasion Resistance of Organic Coatings by Falling Abrasive
  • ASTM D4966 Standard Test Method for Abrasion Resistance of Textile Fabrics
  • ASTM D5181 Standard Test Method for Abrasion Resistance of Printed Matter by the GA-CAT Comprehensive Abrasion Tester
  • ASTM D6279 Standard Test Method for Rub Abrasion Mar Resistance of High Gloss Coatings
  • ASTM D7428 Standard Test Method for Resistance of Fine Aggregate to Degradation by Abrasion in the Micro-Deval Apparatus
  • ASTM F1486 Standard Practice for Determination of Abrasion and Smudge Resistance of Images Produced from Office Products
  • ASTM G65 Standard Test Method for Measuring Abrasion Using the Dry Sand/Rubber Wheel Apparatus
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