MICROSTRUCTURE PARAMETER OF WC-Ni CEMENTED CARBIDE

The quantitative experimental relationships between microstructure parameters and the relationship of Vickers hardness with microstructure parameter were deduced by means of XRD phase analysis, SEM stereological technique and property testing for dual-phase WC-Ni cemented carbide and the simulative γ-phase alloys i.e. the Ni-W-C solution. The result shows that the relation of the γ-phase free path λ with the WC grain contiguity CWC is in opposite correlation and the relation of λ with the γ-phase volume fraction fγ and the WC average grain size LWC is in positive, it shows that the effect of fγ and LWC on the λ~(1-CWC) relation is within the limits of test error, so the structure of dual-phase WC-Ni alloy can be exactly charactered by use of any two parameters among λ (or CWC), fγ and LWC; the relationship of Vickers hardness with microstructure parameter can use the expression HV=3 560+7.00λ-1/2=3 560+2 163·(1-CWC)-1.85=3 560+23.7(f-1γ-1)0.40·L-0.40WC, it is usually accurate enough too.