Formation of microstructure resulting from quasi-peritectic reactions during freezing of Bi–Pb–Sn and Cu–Ni–Sn ternary alloys

The quasi-peritectic reaction, frequently observed in ternary alloy systems, takes the form L + alpha <-> beta + gamma, where L indicates the liquid phase, and alpha, beta and gamma indicate solid phases. The formation of microstructure resulting from the kinetics of this reaction is considered from a theoretical point of view and compared with experimental observations of microstructures formed by quasi-peritectic reactions in two ternary alloy systems, Bi-Pb-Sn and Cu-Ni-Sn. Based on these considerations, an explanation is proposed for experimental observations previously reported in literature concerning phase transformations from the liquid in multicomponent ferrous alloys.