On the analysis of diffuse intensity and striation contrast in electron microscopy images of Al–Cu–Co–Si decagonal phases

Electron microscopy and diffraction experiments were carried out to analyze diffraction features and correlate with the striation contrast observed in the images of Al–Cu–Co–Si decagonal phase. There are two important diffraction features identified which include the diffuse streak and the extra satellite spots. The extra satellite spots can indicate some sort of superlattice chemical ordering among the clusters while the diffuse streaks indicate presence of some kind of phason disorder leading to the observation of striation contrast in the imaging modes.