Wetting of SiC by molten Cu–20Me–2Cr (Me=Ag, Mn, Si, and Sn) alloys at 1373 K

Abstract

Abstract In this work, the effect of the third addition (Ag, Mn, Si, and Sn) on the wettability and the interfacial structures of Cu–20Me–2Cr/SiC systems was investigated. The third addition Me has the obvious effect on the wettability and the spreading dynamics. The sequence of effectiveness is Sn > Ag > Mn > Si. Si Addition can suppress the precipitation of the wettable reaction products, and thus that caused the poor wettability. Although additions of Ag and Mn can improve the wettability significantly, a dissolution zone beneath the reaction layer would be formed. When the third addition Me was thermodynamically repulsive with Si. Meanwhile, the critical concentration of Si in liquid for equilibrium with SiC was less than the corresponding amount of graphite consumed by Cr addition. The dissolution zone would be suppressed. Sn addition satisfied this situation, and thus the best wettability can be achieved. The spreading of Cu–20Me–2Cr/SiC was controlled by the decomposition of SiC rather than the precipitation reaction.