Hardness Testing

Hardness is a measure of the resistance of a material to localized plastic deformation induced by either mechanical indentation or abrasion. It is generally characterized by the microstructural properties of a solid, but the behavior of solid materials under force is complex; therefore, there are different measurements of hardness: scratch hardness, indentation hardness, and rebound hardness.

Hardness testing is used not only for quality control (e.g. of raw material, welded joints,…), but also within failure analysis and reverse engineering, being suitable to give insights on the thermomechanical history of a material or component.

The hardness test and the respective testing machine will be chosen in relation to the material specimen and its expected hardness and geometries.

  • For inherently hard materials: Rockwell testing scale.
  • Less hard materials: Brinell testing scale.
  • For small parts or small sections of specimens: Micro-hardness testing- Vickers or Knoop scale.
  • For coatings and thin layers.

The associated testing machine will be allocated for the test depending on the received specifications of the sample.

Step 700 - UNHT3 Ultra nanoindenter from Anton Paar

The UNHT³ is a nanoindenter that utilizes real force and displacement sensors to analyze a material's mechanical properties at the nanoscale. Its active and exclusive surface referencing system, eliminates the impact of thermal drift and compliance. This makes it well-suited for long-term measurements on all materials ranging from the atomic to the nanoscale, including polymers, thin layers, and coatings.

A large range of indentation depths (from a few nm up to 100 μm) and indentation loads (from a few μN up to 100 mN), and a negligible thermal drift down to 10 fm/sec without any depth correction that allows long-time measurements such as creep tests.

 Instrumented nano-indenter​ and indents in steel surface

Micro-hardness Tester 402 MVD (10 gf - 2 kgf)

Where testing is required for smaller specimen parts and sections, the Micro-hardness Tester 402 MVD unit is more appropriate

The 402 MVD Vickers and Knoop Tester provides an affordable reliable solution for accurate micro-hardness scale testing, both for quality assurance or metallurgical research. The 402 MVD is equipped with an automatic turret and crisp optics that provides a total magnification of 100X and 400X, as well as eight dial selectable test loads ranging from 10 gf - 2 kgf. For easy sample mounting, a 100 × 100 mm precision XY-Stage is employed.

Hardness tester ZHU250 ZwickRoell (1 kgf - 250 kgf)

Hardness testing is possible for a wide range of materials through our combined access to our hardness and micro-hardness testing units. 

For the testing of harder materials, the Hardness tester ZHU250 ZwickRoell (1 kgf – 250 kgf) is available.

he ZHU250’s robust design guarantees testing in a wide range of applications requiring a test load up to 2.5 kN (250 kgf). Optical measuring of indentations uses a digital precision measuring system.

The ZHU250 universal hardness tester is used for the following methods:

  • Vickers (HV) ISO 6507, ASTM E384
  • Knoop (HK) ISO 4545, ASTM E384
  • Brinell (HBW) ISO 6506, ASTM E10
  • Rockwell (HR) ISO 6508, ASTM E18
  • Vickers depth measurement HVT VDI/VDE 2616-1
  • Brinell depth measurement HBT VDI/VDE 2616-1
  • Ball indentation hardness (H) (ISO 2039-1) (plastics)

Hardness and instrumented nanoindentation testing systems in Building 376/R-004