The Knoop hardness test at a glance:
Surface preparation
Before application of the Knoop hardness test, you must prepare the surface of the material to be tested.
The Knoop hardness test is used for micro hardness testing (loads below or equal to 1 kgf) and so the surface of the sample material should be highly polished or electropolished before it is introduced to the micro hardness tester.
Loads
The Knoop micro hardness test should not be used if it produces diagonal lengths less than 20 μm, as this will result in measurement inaccuracy.
When deciding whether to use the Knoop or Vickers micro hardness testing method, there are a few things to consider.
Hardness testing is key in most quality control procedures. That’s why we provide a complete range of hardness testing machines.
All our Knoop micro hardness machines are designed to deliver the long-term performance for which Struers is renowned.
Duramin-4: Manual Micro and Micro/Macro Hardness Testing Machine
Load ranges: 10 gf – 2 kgf, 1 kgf – 62.5 kgf
Duramin-40: Semi-Automatic and Fully Automatic Micro/Macro Hardness Testing Machine
Load ranges: 10 gf – 10 kgf, 10.0 gf – 31.25 kgf, and 1 gf – 62.5 kgf
Duramin-100: Fully Automatic Micro/Macro/Universal Hardness Testing Machine
Load ranges: 10 gf – 62.5 kgf, 10 gf – 150 kgf, 10 gf – 250 kgf
Duramin-600: Semi-Automatic Universal Hardness Tester
Load ranges: 1 – 250 kgf, 3 – 750 kgf, 5 – 3000 kgf
Duramin-650: Semi-Automatic and Fully Automatic Universal Hardness Tester
Load ranges: 1 – 250 kgf, 3 – 750 kgf, 5 – 3000 kgf
If you would like to know more about the hardness testing methods for metallic and other materials, including a full definition of hardness testing, the different applications of hardness tests and how to prepare for hardness tests, download our resources.
Find all you need to know about hardness testing
Download our Hardness Testing Application Note
