The morphology of small particles of the icosahedral phase and their orientation relationship with the surrounding α-Al matrix in melt-spun Al-3Cu-1.5Li-1Mg alloys have been investigated, as-spun and after heat treatment, by detailed transmission electron microscopy. The icosahedral phase particles in as-spun Al-3Cu-1.5Li-1Mg are nearly spherical in shape. After heat treatment in the temperature range of 300 to 400°C, the icosahedral phase particles change their morphology into a variety of rod and faceted shapes. The resulting faceted growth shapes are quite different from the triacontrahedron shape reported previously for conventionally solidified particles of the Al6CuLi3 phase. The icosahedral phase particles in Al-3Cu-1.5Li-1Mg as-spun and after heat treatment exhibit four different orientation relationships with the surrounding α-Al matrix indicating that the icosahedral phase particles nucleate heterogeneously on growing primary α-Al cells and dendrites during rapid solidification.
|Number of pages||15|
|Journal||International Journal of Rapid Solidification|
|Publication status||Published - 1992 Dec 1|
All Science Journal Classification (ASJC) codes