Application of three-dimensional electron tomography using bright-field imaging-Two types of Si-phases in Al-Si alloy

When a dilute amount of Si is added to Al, it results in the precipitation of Si-phases, either planar- and/or rod-type, depending on the ageing conditions. Observation of these phases had been carried out by TEM two dimensionally so far; nevertheless information of the thickness as well as the distribution had been neglected in the past. In this paper, a combination of electron diffraction, high-resolution transmission electron microscopy, and three-dimensional electron tomography was applied to characterize the morphologies and the orientation relationship of the Si-phases in an Al-Si alloy.