THE WETTABILITY AND THE REACTION FOR SIC PARTICLE/AL ALLOY SYSTEM

The incorporation process and the wettability for an SiC particles/aluminium alloy system were measured. The wettability between SiC particle and liquid aluminium was evaluated by the time required for the particulate incorporation. The incorporation time could be measured from a stirring time-melt temperature chart. Magnesium and titanium shortened the incorporation time of alpha -SiC particles into liquid aluminium and improved the wettability because of their strong affinity for SiC. Copper and zinc prolonged the incorporation time and no reaction products were found in the matrix. Furthermore, surface active elements with weak affinity for SiC (lead and bismuth) extremely prolonged the incorporation time because these elements prevent the reaction at the interface, whereas lithium shortened the incorporation time remarkably.