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HomeProductsHard Materials BusinessKH Hard Alloys > What are KH hard alloys?

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

KH powder

Vacuum sintering furnace

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