Hardness Measurement Techniques

Sep 24
12:37

2015

Presto

Presto

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Hardness of a product is measured to check the solid matter resistance to various permanent shapes when a specific amount of force is applied. Some products such as metal are harder than they appear and in comparison with other products too. In general, macroscopic hardness of a product is characterized by the strong bond in the molecules known as intermolecular bond, but at the same time, the behavior of materials kept under force is difficult to measure.

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Hardness of a product is measured to check the solid matter resistance to various permanent shapes when a specific amount of force is applied. Some products such as metal are harder than they appear and in comparison with other products too. In general,Hardness Measurement Techniques Articles macroscopic hardness of a product is characterized by the strong bond in the molecules known as intermolecular bond, but at the same time, the behavior of materials kept under force is  difficult to measure. Hence, numerous types of measurement tests are introduced like Scratch hardness Test, Indentation hardness test and rebound hardness.

Hardness is mainly dependent on the elastic stiffness, ductility, strain, plasticity, toughness, strength, viscosity and viscoelasticity. Common examples of hard matter are concrete, ceramics, super hard materials, some types of metals which can be contrasted with soft matter. Here, we will discuss the three types of hardness measurements: Rebound, Scratch and Indentation. In all the three types of measurement, different measurement scales are used.

Scratch hardness

Scratch hardness is the measure of how resistant a test specimen is to permanent deformation or fracture due to friction from a sharp object. The principle objective behind the scratch hardness includes the method of scratching an object made of softer material with the object made of harder material. Scratch hardness means that the force required to cut the material to the substrate. The most common test method used to determine the Scratch Hardness is Mohs scale. The tool used to make the measurement is the Scratch Hardness Tester.

Indentation Hardness

Indentation hardness helps to measure the resistance of a sample to material deformation due to a constant compression load from a sharp object. This type of hardness testing is done mainly on metal components and other alloys and also used in the engineering field. The test is done mainly to measure the primary factors of indentation done with the specifically dimensioned and loaded indenter.  The popular indentation hardness measurement scales are Shore, Rockwell, Brinell and Vickers.

Rebound Hardness

Rebound hardness is also known as dynamic hardness which is done to measure the elevation in “bounces” of a diamond shaped hammer which is dropped from a predetermined or standard height on a specimen. This helps to check the elasticity of a product. The most popular testing instrument used to perform rebound hardness test is a Rebound Resilience Tester.

To test the hardness of different materials, there are numerous hardness testers that are manufactured and supplied by the manufacturers. To choose the best one, one can also surf online.