EFFECTS OF Va GROUP AND VIa GROUP ELEMENTS ON THE WETTABILITY BETWEEN SiC AND MOLTEN ALUMINUM.

The wettability of molten aluminum alloys containing 5% V, Nb and Ta in Va group and Cr, Mo and W in VIa group was measured. Wetting of SiC in all the alloys occurs after a certain period. The period is shortened by alloying all elements of Va and VIa groups. These elements without Cr accelerate the wetting rate. EPMA analysis shows formation of (V//2C plus V) and TaC in the alloys containing V and Ta respectively. The reaction rate is expressed by an equation which is proportional to the number of nuclei for wetting per unit interfacial area and unwetted ratio of the interface (1 minus alpha ). Activation energy for wetting is approximately 330 kJ/mol.