Pressure Infiltration of Silver Into Compacts of Oxidised SiC

摘要

Pressure infiltration of liquid silver, with an oxygen content near saturation, into compacts of oxidised SiC has been investigated. The experimental results indicate that the threshold pressure is significantly reduced with respect to the case of unoxidised SiC. On the other hand, the infiltrated height increases at a much higher pace with the pressure drop in compacts of oxidised SiC, indicating that the compact permeability is also higher. Evaluating the intrinsic permeability of compacts of oxidised and unoxidised SiC by means of pressureless infiltration of an organic fluid led to results that differ in ≈10%. This suggests that the poorer infiltration kinetics observed in the unoxidised case should be ascribed to the reduction in the metal/ceramic contact area promoted by the gas evolved in the reaction between the oxygen dissolved in silver and unoxidised SiC.