| Used the graphite die, steel mould, water-cooled copper mold and rapid solidification method, etc., and metallographic microscopy, scanning electron microscopy (SEM), X-ray diffraction analysis and detection methods to systematically study the characteristics of the microstructure, phase composition of Sn-3.5Ag eutectic alloy under the conditions of different solidification rate. The results show that Sn-3.5Ag eutectic alloy is composed by β-Sn phase and Ag3Sn phase. The microstructure is the regular arrangement of lamellar-type structures for graphite die cooling; The microstructure is the small block structure for metal mould and water-cooled copper mold cooling; when the solidification rate reached rejection with rapid solidification, the microstructure is finer block structure. |
