The crystal morphology of fibrous silicon in strontium-modified Al-Si eutectic

Abstract

The crystallography of silicon in strontium-modified Al-Si eutectic has been studied by transmission electron microscopy. Strontium addition results in a massive increase in twin density in the silicon phase, and the twin density increases with cooling rate for fixed strontium content Growth of the fibrous eutectic silicon is shown to be compatible with the twin-plane reentrant edge growth mechanism. Branching mechanisms are described. No consistent orientation relationships between the eutectic phases were observed, but the aluminium phase exhibited a 〈110〉 texture.