The work carried out on pressure infiltration of packed ceramicparticulate by liquid metals, mainly aluminum and its alloys, is reviewed. Thetheoretical background and the main features of the technique and of theexperimental procedures are first considered. The experimental results obtainedby several authors approximately follow Darcy and capillary laws. Thedistinguishable roles of the key variables of the infiltration process are illustratedby means of selected experimental results. These variables can be classifiedaccording to their origin (a) ceramic particulate (size and shape, surfacecondition), (b) liquid metal (surface tension, etc.), (c) liquid/solid interface(contact angle, reactivity, etc.), and (d) experimental variables (pressure,temperature, etc.). In particular, the importance of the particulate shape and sizedistribution, the surface tension of the liquid metal, the contact angle, and theoxide layer, in the case of aluminum, is highlighted. Results for binary aluminumalloys and alloys of technological interest (AlMgSi and AlCu alloys) are alsodiscussed. Comparison of results for other metals with those for aluminumthrows light on several aspects of the infiltration process. Of particular interest issilver, a metal having a behavior with respect to oxygen opposite to that ofaluminum.
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