Wettability of Sic by Liquid Pure Metals

The wettability of three kinds of SiC such as a reaction bonded SiC, a hot pressed SiC and a single crystal of α-SiC by liquid metals (Pb, Sn, Al, Si, Au, Ge, Ag, Fe, Ni and Co) was measured by the sessile drop method. Wettability was evaluated by the contact angle of liquid metal on SiC. The main results obtained are as follows: (1) Contact angles of liquid pure Pb, Sn, Au and Ag were larger than 90° for all kinds of SiC examined. (2) Reactivity of reaction bonded SiC with liquid metals may be controlled by the carbon treatment, which carburates the surface of the SiC. (3) Contact angles of liquid pure Fe, Co and Ni were always smaller than 90° for both the reaction bonded SiC and the hot pressed SiC. (4) Contact angle of liquid pure Al on a single crystal of α-SiC changed considerably with time elapsing. The initial contact angle was 160°, reducing gradually with time, the final one after 6.9 ks was 56°. (5) Contact angle of liquid pure Ge depended on the kind of SiC used. The contact angle was obtuse on hot pressed SiC and α-SiC, while it was acute on reaction bonded SiC. (6) Wetting behavior of liquid metals on SiC closely is related to the solubility of Si and C.