Wetting of ceramic particulates with liquid aluminum alloys: Part I. Experimental techniques

An experimental technique for evaluation of wettability of solid particulates with liquid metal was developed. Uniformly packed powder specimens were prepared with a tamping device specially made for the present experiment, and wetting tests were conducted by pressure infiltration of liquid Al-alloys into the powder specimens. The threshold pressure for infiltration was used as a measure of wettability. With this technique, wettabilities were measured for 10 μm diameter SiC and B₄C particulates by several Al-based alloys. Threshold pressures obtained from this technique showed reproducibility to approximately ±7 kPa. Microstructures of infiltrated powder specimens indicated planar front infiltration with no disruption of powder compact during infiltration test and virtually no porosity.