ASTM E834

Introducing ASTM E834-11 - Industrial Physics

ASTM E834-11 is a global ASTM international standard test method to measure the knoop and vickers microhardness of metallic materials.

When you need to know just how tough a sample is - and how well it will resist penetration - microhardness testing is the obvious choice.

Microhardness testing is a method of determining a material’s hardness or resistance to deformation. The ASTM E834-11 standard outlines an effective and reliable approach for knoop and vickers microhardness testing.

What is knoop hardness testing to ASTM standards?

Knoop hardness testing uses an elongated, rectangular shaped indenter. It’s pushed into the surface of a sample to produce an indentation which is then measured. Unlike the vickers testing method, the knoop test uses only the long axis when calculating the indentation as a hardness indicator.

The ASTM E834-11 knoop test is often performed with lighter loads. The shape of the hardness testing probe means it’s suitable for samples that need the indentations to be close together, or on the edge of a sample. It can also offer higher levels of precision than the vickers testing method, as the longitudinal diagonal of the indenter is greater. Careful sample preparation to ASTM standards is necessary to ensure that the results remain accurate.

What is vickers hardness testing to ASTM standards?

The vickers hardness test is similar to knoop testing but it uses a differently shaped indenter. The vickers indenter is shaped like a squat pyramid and is typically pressed into the surface of the material for 10 seconds. The amount of force used is of a predetermined amount and varies depending on the materials being tested.

Once the time is up, the indentation left in the sample is analyzed optically to measure the lengths of the diagonals. These are then used to calculate the size of the impression. Vickers testing isn’t suitable for coating thicknesses under 60 microns.

For more information on microhardness testing, visit our blog by clicking here.

ASTM E834-11 testing equipment

So, how can Industrial Physics improve your ASTM E834-11 testing?

Tru-Blue mVT (MicroVT)

A semi-automated microhardness testing system. It measures hardness values on the vickers (HV) and knoop (HK) scales from 10g up to 1000g (1kg).

Our state-of-the-art electronics and high-quality optical displays make running tests quick and easy. And our microhardness testing devices give you accurate and repeatable results.

Your global test and inspection partner for ASTM E834-11