Three-dimensional morphology and formation process of icosahedral quasicrystal phase have been investigated in a melt-spun Al-18 Mn alloy(in wt%).Three distinct layers corresponding to varying temperature gradient have been observed on the cross section of the ribbons.3D morphologies of cellular and dendritic icosahedral phase have been obtained through electro-etching.A model has been proposed to describe the formation process of the icosahedral phase and α-Al during the rapid solidification.The icosahedral phases are primarily precipitated from the melt into fine cellular and dendritic particles,and subsequently engulfed by the α-Al which propagates in a planar morphology.
Three-dimensional morphology and formation process of icosahedral quasicrystal phase have been investigated in a melt-spun AI-18Mn alloy (in wt%). Three distinct layers corresponding to varying temperature gradient have been observed on the cross section of the ribbons. 3D morphologies of cellular and dendritic icosahedral phase have been obtained through electro-etching. A model has been proposed to describe the formation process of the icosahedral phase and a-A1 during the rapid solidification. The icosahedral phases are primarily precipitated from the melt into fine cellular and dendritic particles, and subsequently engulfed by the a-A1 which propagates in a planar morphology.