作者:Á Révész、G Heunen、L.K Varga、S Suriñach、M.D Baró
DOI:10.1016/j.jallcom.2003.07.021
日期:2004.4
The crystallization of Al85Ce5Ni8Co2 and Al85Y5Ni8Co2 alloys was studied using differential scanning calorimetry (DSC) and in situ X-ray diffraction (XRD). Continuous heating DSC measurements revealed that Al85Ce5Ni8Co2 and Al85Y5Ni8Co2, alloys exhibit a glass transition followed by a super-cooled liquid region where crystallization occurs through a two- and three-stage process, respectively. The crystallization sequences were also observed in situ by means of XRD using a third generation synchrotron source. During the first crystallization stage, the primary precipitation of alpha-Al takes place only in the Al85Y5Ni8Co2 alloy while in the Al85Ce5Ni8Co2 alloy, a simultaneous precipitation of a metastable Al11Ce3 and alpha-Al was observed. The final microstructure contained alpha-Al, Al3Y/Ce, Al9Co2, and Al3Ni phases. The crystallization was monitored both during heating of the amorphous alloy and during cooling of the liquid alloy in order to detect possible differences in the nature of the crystallization. (C) 2003 Elsevier B.V. All rights reserved.