Ceramic Hardness Hv

The method for measuring the hardness of fine ceramics is defined in jis r 1610 iso 14705.

Ceramic hardness hv.

In fact many ceramic specifications list minimum hardness requirements. Often hardness of ceramic material as with other materials is directly equated to wear resistance. 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. Where f applied load kg.

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. Hv 1 854 f d. This has led to the use of fine ceramics in. 440hv30 or xxxhvyy zz if duration of force differs from 10 s to 15 s e g.

440 is the hardness number hv gives the hardness scale vickers 30 indicates the load used in kgf. Hardness of ceramic materials is usually tested by vickers or knoop methods using diamond indenters. Hardness is an important parameter correlating with wear resistance of the mate. 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.

Extreme hardness is the primary feature that endows fine ceramics with their superior wear resistance. Vickers hardness numbers are reported as xxxhvyy e g. 20 indicates the loading time if it differs from 10 s to 15 s.