BEHAVIOR OF PARTICLES AT SOLIDIFICATION INTERFACE OF ALUMINUM MATRIX COMPOSITES
铝基复合材料中颗粒在凝固界面的行为

The behavior of particles at solidification interface of Al/Al2O3 and Al-Si/Al2O3 composites was studied by using the zone-melting unidirectional solidification method. The particles were pushed by S/L interface in most of the composites, but the state of particle engulfment was realized by adding minute elements into an Al-Si/Al2O3 composite. An explanation model based on interfacial energies was proposed. If the contact angle between a solidification front and a particle is more than 90°, the particle can be engulfed into the solid. Otherwise the particle would be pushed.