KH hard alloys are our proprietary hard materials manufactured using the powder metallurgy technology developed by the R&D Center of Toyo Kohan Co., Ltd.
As shown in the figure right, KH is a cermet hard material consisting of a hard phase made of biboride ceramic particles and a binder phase made of a metal equivalent to stainless steel. Due to its high degree of hardness, it has both superior abrasion and corrosion resistant properties.
In addition, the characteristics of the metal binder phase enable the metal layer to be firmly joined to steel by diffusion-bonding without using brazing filler metal.
Photo: Diffusion-bonding of steel
Manufacturing method of hard materials
KH does not harden through heat treatments in the same manner as steel. Instead, it is hardened by producing hard ceramic, which is created by sintering metal powder, as follows:
Cylinder immediately after shrinkage fitting
Screw during processing
Vacuum sintering furnace