Hardness Testing Reference Materials

General Information

Hardness is the measure of resistance to deformation when an external force or load is applied to a particular material.

There are many methods of applying force to a material to conduct a hardness test, the most common of which are:

Testing Method Information (PDF) ISO Standard ASTM Standard
Brinell PDF ISO 6506 ASTM E10
Vickers PDF ISO 6507 ASTM E384
Rockwell PDF ISO 6508 ASTM E18
Rockwell Superficial PDF ISO 6508 ASTM E18

The 30 Rockwell test scales and their suggested applications are available here.PDF

Unlike physical quantities such as length, time, volume or electrical current, hardness is a relative value that has no fundamental quantity or absolute standard. Hardness is related to other mechanical characteristics such as:

  • Tensile strength
  • Yield strength
  • Elastic limit
  • Resistance to wear
  • Ductility

Hardness has become as critical as fit and finish in determining product quality. Metallic parts must function under increasingly arduous conditions, with loads, pressure and temperatures constantly increasing; hardness measurement is an easy and effective way of establishing that components will be able to take the strain.

Interactive Tools

We've taken some of the calculations commonly required when using or purchasing a hardness tester, converted them into interactive online tools and made them available to users.

To try our interactive tools, either click "Read more" for the menu, or use the "Interactive Tools" panel on the right to go straight to a particular tool.


Comparison Between Testing Methods

Each testing method has its own strengths and weaknesses. To help users find the best testing method for their purposes, we have produced a comparison page setting out the pros and cons of each testing method.