Structure and properties of magnesium-matrix composites

Magnesium and magnesium-alloy composites reinforced with SiC particles have been fabricated by a powder metallurgy route involving low-energy mechanical alloying as well as dry mixing, and by the ingot metallurgy route based on a fluxless melting technology. Tensile and instrumented impact tests supplemented by optical and scanning-electron fractography and oblique-section metallography have been used to assess the role of particle/matrix interface reinforcement and the matrix on the crack initiation and propagation behavior. Of the routes employed, low-energy mechanical alloying provided the best property combination.