ISSN:
1662-9752
Source:
Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
In the present work, rapidly solidified alloys strips with Al-0.24Ti and Al-21Si-0.24Ti(inwt.%) were prepared by single roller melt-spinning method. The microstructures, phase andmorphology characteristics of the resultant strips were characterized by means of scanning electronmicroscopy (SEM),transmission electric microscopy (TEM) and XRD technique. The results showthat the grains have been refined after rapid solidification processing, and the micro-nanocrystallinegrain are formed. The morphology characteristics can be changed. The microstructures of Al-0.24Tialloys strip are micro-nanostructure α-Al solid solutions which are similar with granular or nodular,the corresponding SAD pattern is rings, it presents characteristic of polycrystal; Compared withequilibrium solidification, the microstructures of hypereutectic Al-Si alloy are changed obviously.They are composed of primary micro-nanostructure α-Al supersaturated solid solution andnanocrystal granular (α+Si) eutectic which set in the supersaturated solid solution. The nucleation andgrowth of primary silicon are suppressed and primary silicon can not precipitate, meanwhile, α-Alphase is nucleated which prior to eutectic, therefore the microstructures become into the metastablestate. The mechanism of the formation for microstructures of melt-spinning alloys has also beendiscussed
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/02/18/transtech_doi~10.4028%252Fwww.scientific.net%252FMSF.575-578.27.pdf
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