TRANSMISSION ELECTRON-MICROSCOPE OBSERVATIONS OF RECTANGULAR DISLOCATION NETWORKS IN AN AL70CO15NI15 DECAGONAL QUASI-CRYSTAL

The electron diffraction contrast of two types of rectangular dislocation networks in an Al70Co15Ni15 decagonal quasicrystal has been analyzed. One type of dislocation network consists of two dislocation sets whose Burgers vectors are parallel to the tenfold axis A10 and a twofold axis A2D. The other type of dislocation network consists of two dislocation sets whose Burgers vectors are parallel to the A10 and the other twofold axis of A2P. The characteristics of the diffraction contrast of the dislocation networks in the Al-Co-Ni decagonal phase are similar to those in conventional crystals.