Hardness Testing

Most hardness tests consist of the penetration of the metal surface by a very hard indenter under load. The size of the resultant indent, with due regard for the applied load, is a measure of the hardness of the metal. Hardness can thus be defined as the resistance to indentation of a material. We offer a suite of Hardness tests

OUR SUITE OF HARDNESS TESTS

VIKERS HARDNESS TEST

The Vickers hardness test employs a pyramidal diamond indenter with a variety of loads, typically from 1 to 120 kg. Both diagonals of the indent must be measured and averaged and the resulting measure is used to compute the Vickers hardness. Compared to the various Rockwell methods, the Vickers method is slow to perform and requires a good surface finish. however, the Vickers hardness test method is independent of the load employed and far less subject to error than many other hardness test methods.

ROCKWELL HARDNESS TEST

The Rockwell ‘C’ scale is employed for hardened steels, a conical diamond indenter is brought into contact with the metal surface under a load of 150 kg. For softer materials, the Rockwell ‘B’ scale is employed, with a hardened steel ball indenter under a load of 100kg. In both of the above cases, the displacement of the indenter gives the hardness of the material. This is a rapid hardness test method that will work adequately on a normal machined surface. Errors can arise due to movement of the test sample under load. This method cannot be employed on very small or very thin samples, due to the high test load.

BRINELL HARDNESS TEST

The Brinell hardness test method is ideal for use on castings, as it is almost unaffected by surface finish. A hardened steel ball, 10mm in diameter, is the indenter with a 3000kg load. The diameter of the indent is measured and the hardness computed. Any materials whose hardness is close to or exceeds that of the hardened ball cannot be measured by this method

MICRO HARDNESS TEST

This is, effectively, Vickers hardness testing at loads of 1kg or less. This method is typically used to measure the hardness in the case hardened layer, and also of samples of small cross sectional area. Samples must be mounted and prepared for metallography (see above) before hardness testing

Testing Rates

  • Hardness Test – €20 per test carries out
  • Hardness Test: Initial Setup – €50 fixed charge per test type (Not Applicable to Micro Hardness Testing)
  • Hardness Test: Test Mounting – €90 fixed charge (Applicable to Micro Hardness Testing Only)