Melting of multiphase nano-scaled particles embedded in Al matrix: Case of Pb–Sn and Bi–Sn alloys

Two-phase alloys consisting of particles of nanometric size embedded in aluminum matrix were prepared by rapid solidification processing. Electron microscopic studies suggest that at least one of the phases exhibits a well-defined orientation relationship with the aluminum matrix. In situ heating studies carried out in order to study the melting transition and the role of different interphase interfaces during melting shows that for lead–tin two-phase alloys, melting initiates at the triple line and spreads along the eutectic two-phase interface. However, for bismuth–tin two-phase alloys, the melt initially spreads along the matrix–particle interface leading to a core shell microstructure.