Alumina ceramic is a very high hardness material, its hardness is usually between 1700-2000HV. This means that alumina ceramics can resist high pressure and wear, and can maintain the finish of the surface.

The hardness of alumina ceramics is generally 9 to 9.5, which is close to the top of the Mohs hardness scale, second only to diamond. ‌ The hardness value of alumina ceramics is usually between 9 and 9.5, which is determined by their crystal structure and composition ‌.

According to different test methods and standards, the hardness of alumina ceramics is also different. For example, studies have shown that the hardness of alumina ceramics can reach 2000-2300 MPa, compared with the hardness of ordinary steel is only 120-180 MPa ‌.

In addition, the Rockwell hardness of alumina ceramics is HRA80-90, the hardness is second only to diamond, far exceeding the wear resistance of wear-resistant steel and stainless steel ‌.

These data show that alumina ceramics perform well in terms of wear resistance and are able to resist external scratches and wear on their surfaces, thereby extending their service life ‌.

Alumina ceramic is a material with extremely high hardness, and its hardness index is much higher than most metals and other ceramic materials. In industrial and technological applications, alumina ceramics are widely used to manufacture a variety of wear-resistant, high-temperature and corrosion-resistant parts and materials.

According to different test methods and standards, the hardness of alumina ceramics is also different. For example, studies have shown that the hardness of alumina ceramics can reach 2000-2300 MPa, compared to the hardness of ordinary steel is only 120-180 MPa. This means that the surface of alumina ceramics is difficult to be scraped or worn, and has excellent wear resistance.

The hardness of alumina ceramics makes it have excellent high temperature resistance. Because alumina ceramics have a dense structure, clear grain boundaries and a melting point of up to 2072 degrees Celsius, they can withstand extremely high temperatures and thermal shocks. Therefore, under high temperature environment, alumina ceramics can still maintain its mechanical properties and stability, and it is not easy to deformation or fracture.

In addition, alumina ceramics also have excellent corrosion resistance. Due to their chemical stability and high hardness, alumina ceramics exhibit extremely high corrosion resistance under attack by acids, bases and other chemicals. This makes alumina ceramics an ideal material for the manufacture of acid-alkali resistant containers, chemical equipment and medical devices.

In addition to the above characteristics, alumina ceramics also have good insulation properties, low thermal extension coefficient, high toughness and low density characteristics, so that it is widely used in electronics, optics, aerospace and other fields.