Abstract:A two-phase numerical model coupled with heat transfer was presented to describe the radial distribution of SiC particles on centrifugally-cast metal matrix composite, and a transverse static magnetic field was concurrently imposed to induce electromagnetic stirring of the melt as it revolved with the mold. Meanwhile, experimental observations were also carried out to examine the radial distribution of SiC particles in pure aluminum. The effects of the imposed magnetic field, particle size and the matrix metals were discussed. The computational results show that the particles tend to be congregated by the centrifugal force, and both increasing the imposed magnetic field and decreasing the particle size tend to result in even distribution of the particles. With the magnetic field varying from 0 to 1 T and the particle size from 550 to 180 μm, a uniform distribution of the particles in the aluminum matrix can be obtained among the computational results. The matrix metal can also influence the particle distributions due to the difference in physical properties of metals. Experimental observation shows similar tendency of particle distributions in aluminum matrix influenced by magnetic field and particle size. However, the chilling effect from the mold wall results in an outer particle-free zone, which is not involved in the numerical model.

Key words: electromagnetic centrifugal casting; numerical model; particle distribution; composite