Hardness is a simple and effective method to evaluate the mechanical properties of materials, which has been used for more than one hundred years. But the definition of hardness has not been unified at present. From the form of action, it can be defined as "a measure of the ability of an object to resist the deformation of another object"; Deformation mechanism can be defined as "the ability to resist elastic deformation, plastic deformation and failure" or "the ability of materials to resist residual deformation and failure". In any case, when measuring the hardness of a solid material, a hard object with a certain shape and size, that is, a pressure head, always contacts the surface of the measured material with a certain pressure. Hardness measurement is not only related to the mechanical properties of materials such as elastic modulus, yield strength and tensile strength, but also closely related to the measuring conditions of the measuring instrument itself. Therefore, hardness itself is not a physical quantity, but the overall performance of local mechanical properties of materials under specific conditions. It is the expression of local resistance of materials to mechanical action (pressing or scoring) of external objects.

Also known as indentation tester/hardness tester/microscope hardness tester/ultramicro hardness tester/dynamic ultramicro hardness tester/nano hardness tester/nano indentation tester, etc. Used to characterize the mechanical properties and product quality of various coatings and films, including hardness, elastic modulus and fracture toughness. The characterized materials include almost all types of materials: soft, hard, brittle or ductile materials.