Ceramic Hardness Hv

440 is the hardness number hv gives the hardness scale vickers 30 indicates the load used in kgf.

Ceramic hardness hv.

440hv30 or xxxhvyy zz if duration of force differs from 10 s to 15 s e g. Extreme hardness is the primary feature that endows fine ceramics with their superior wear resistance. Vickers hardness calculator hardness is a measure of the resistance of a material to plastic deformation induced by applied forces. In fact many ceramic specifications list minimum hardness requirements.

The method for measuring the hardness of fine ceramics is defined in jis r 1610 iso 14705. Vickers hardness is a resistance value obtained by pressing a diamond indenter onto a test specimen. Hardness of ceramic materials is usually tested by vickers or knoop methods using diamond indenters. Hv 1 854 f d.

For example a new astm zirconia specification for surgical implants f 1873 98 stipulates that vickers hardness hv shall be no less than 11 8 gpa 1200 kgf mm 2 at a load of 9 8 n 1 kgf. Vickers hardness numbers are reported as xxxhvyy e g. The hardness of ceramic materials is a property which is of high significance as it relates to the ability of the material to withstand penetration of the surface through a combination of brittle fracture and plastic flow. 20 indicates the loading time if it differs from 10 s to 15 s.

In this test a hardened steel or tungsten carbide for extremely hard materials ball of 2 5 5 or 10 mm in diameter is used as indenter. Hardness is an important parameter correlating with wear resistance of the mate. Metals ceramics are harder than others e g.