Hardness can be defined as how much the surface of any material is resistive to scratches, dents, and bends. It is a surface phenomenon, and it is not related to stresses. It only shows how much surface of any material is resistive to scratches.
There are different measurements of hardness: scratch hardness, indentation hardness, and rebound hardness.
Scratch hardness: Scratch hardness is the measure of how resistant a sample is to fracture or permanent plastic deformation due to friction from a sharp object. The principle is that an object made of a harder material will scratch an object made of a softer material. The most common test is Mohs scale, which is used in mineralogy. One tool to make this measurement is the sclerometer.
Indention hardness: Indentation hardness measures the resistance of a sample to material deformation due to a constant compression load from a sharp object; they are primarily used in engineering and metallurgy fields. Common indentation hardness scales are Rockwell, Vickers, Shore, and Brinell.
Rebound hardness: Rebound hardness, also known as dynamic hardness, measures the height of the "bounce" of a diamond-tipped hammer dropped from a fixed height onto a material. This type of hardness is related to elasticity. The device used to take this measurement is known as a scleroscope.
There are different measurements of hardness: scratch hardness, indentation hardness, and rebound hardness.
Scratch hardness: Scratch hardness is the measure of how resistant a sample is to fracture or permanent plastic deformation due to friction from a sharp object. The principle is that an object made of a harder material will scratch an object made of a softer material. The most common test is Mohs scale, which is used in mineralogy. One tool to make this measurement is the sclerometer.
Indention hardness: Indentation hardness measures the resistance of a sample to material deformation due to a constant compression load from a sharp object; they are primarily used in engineering and metallurgy fields. Common indentation hardness scales are Rockwell, Vickers, Shore, and Brinell.
Rebound hardness: Rebound hardness, also known as dynamic hardness, measures the height of the "bounce" of a diamond-tipped hammer dropped from a fixed height onto a material. This type of hardness is related to elasticity. The device used to take this measurement is known as a scleroscope.
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