Hardness Testing

Test Center | Accreditation | Tensile Testing | Metallurgical Testing

What it's all about...
Hardness testing, which includes Brinell, Rockwell , Leeb and Microhardness (Knoop) measures hardness by impressing an indentor into the surface of the material under a specified load.

  • Brinell testing measures hardness by impressing a 10mm tungsten carbide ball into the surface of the material with a 3000kg load. The diameter of the impression is measured with a portable microscope and converted into a Brinell Hardness Number (HBW). Testing is in accordance with ASTM E10 and A370.
  • Rockwell testing measures hardness by pressing either a 1/16" diameter steel ball or a diamond penetrator into the material surface. The Rockwell test measures the depth of the penetration and hardness is read directly on a dial or digital readout. Testing is conducted in accordance with ASTM E18.
  • Microhardness (Knoop) measures hardness by pressing a tiny diamond indentor into the surface of a sample which has been highly polished and mounted in a plastic holder. The indentor leaves a diamond-shaped impression which must be measured under a microscope at a magnification of 200X. Testing is performed in accordance with ASTM E384.
  • Leeb testing measures hardness by using a calibrated instrument that impacts a diamond tipped body (generated by a spring force) onto the surface of the material to be tested. The ratio of the rebound velocity to the impact velocity is a measure of the hardness. Hardness is indicated on an electronic digital display. Testing is performed in accordance with ASTM A956.

Capabilities

  • Three 4-post hydraulic brinell machines can handle bars up to 12" diameter. One tabletop hydraulic brinell machine is used for testing small sections and samples.
  • Rockwell hardness testing to the B, C, 15Tand 15N scales is conducted on three Wilson Rockwell hardness testers.
  • Portable hardness testers include a Riehle portable Rockwell tester and an Equotip Leeb hardness tester.
  • Microhardness testing is performed on a Wilson Knoop hardness tester.