Capacitance monitoring of the infiltration of ceramic Particulate Preforms with Liquid Metals at 750 to 850 °C

The authors previously developed a capacitance technique to determine the position of the infiltration front as a function of time during the pressure infiltration of ceramic particulate preforms with liquid metals. In the present work, the technique was extended to higher temperatures and was used to monitor the infiltration of alumina particulate preforms with Al-Mg alloys and silicon carbide particulate pre-forms with Sn and an Al-Si alloy. The infiltration front position could be determined in the alumina pre-forms. However, it was not possible to clearly interpret the results obtained from the infiltration of semiconducting silicon carbide preforms. The observed range of capacitance circuit voltage to infiltra-tion distance ratios agreed with the predicted range for both simulated and alumina preform infiltration experiments. Formation of unstable infiltration fronts could also be detected.