Definition - What does Barcol Hardness mean?
This is the measurement of the degree of hardness of a material determined by the use of the Barcol impressor scale. This quantity can be used to measure the hardness of materials like:
- Plastic and polymers (duro-plastics and thermos-plastics)
- Soft metals and alloys (aluminum)
- Finished and semi-finished products
The scale meets the ASTM and NFPA standards for use in testing of material hardness.
Corrosionpedia explains Barcol Hardness
The hardness of a material is determined by the ease of the material to deform or scratch. This resistance to plastic deformation is included in the properties of the material and thus helps in material selection in the engineering and construction fields.
This is an indentation-type of hardness, where pressure is uniformly applied on the surface of a specimen to the dial indicator maximum reading. The depth of penetration or indentation is then converted into an absolute Barcol number. The Barcol number is automatically generated by the measuring equipment. The testers are available in a range of models depending on the nature of materials to be tested.
The indenter point is placed perpendicular to the surface being tested. Light pressures are exerted in the measuring instrument, driving the spring loaded indenter point into the surface. The spring effect leads to the indication of the hardness on the dial. The data is directly obtained, hence making Barcol hardness an easy-to-measure property of materials.