Binder Composition and Carbon Content

Although the hardness of hardmetal is determined mostly by the carbide phase (see Section 8.3.1), the hardness of the binder does contribute to the overall hardness of the material. Therefore the composition of the binder, and. specifically the amount of W dissolved in the binder, affects the overall hardness. 

The composition of the binder depends on the total carbon content of the material since, according to Exner [18], there seems to exist a reciprocal relationship between 

The hardness of materials produced via powder metallurgy is known to decrease with increasing porosity level. However, hardmetals are almost pore-free materials and variations in their extremely low level of porosity does not affect their hardness appreciably. 

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