① Brinell hardness (HB) : Brinell hardness is a type of hardness measurement for metallic materials. The Brinell hardness test uses a hard, spherical indenter to compress the surface of the metal sample under a specific load. The resulting permanent indentation is then measured and converted into a Brinell hardness number.
It is suitable for measuring the hardness of large, brittle and cast iron. The indentation diameter is generally D=12.70mm (0.500in).
② Rockwell hardness (HRC) : The Rockwell hardness test uses a hard, spherical indenter to compress the surface of the metal sample under a specific load. The resulting permanent indentation is then measured and converted into a Rockwell hardness number.
It is suitable for measuring the hardness of small, hard and difficult-to-machine materials. There are three types: A type (60kgf), B type (100kgf) and C type (150kgf).