Pre-nucleation clusters mediated crystallization in Al-Si melts

Typical (HR)TEM images showing the remains of pre-nucleation clusters, nanometer-sized particles, in the silicon grains of commercial purity Al-10Si alloy (a) and high purity Al-10Si alloy (b). The inset at the bottom right corner is the FFT of panel a, and the right middle inset is the low magnification image of the silicon grain in panel a. The others insets are FFTs of corresponding nanometer-sized particles indicated by black arrows. The white arrows give the d-spacings of corresponding nanometer-sized particles. The blue arrows indicate {1 1 1} plane of silicon crystal.614