Decagonal quasicrystal growth in chill cast Al 72Ni 12Co 16 alloy

Abstract

The single-phase decagonal quasicrystal alloy Al 72Ni 12Co 16 was melted by containerless processing and chilled on a copper substrate in an electromagnetic facility. X-ray, TEM, and SEM techniques were used to investigate the microstructure and identify the phase composition. The approximately directionally solidified decagonal quasicrystal in the chill cast sample showed facet morphology and grew in a lateral growth mode along the twofold axis normal to the plane (00002). The experimental results fit well with the prediction of Toner’s theoretical atomistic growth model.