Rapidly quenched Mg(65)Al(x)CU(25-x)MM(10) (MM : mischmetal) alloys

The ductility of the amorphous Mg-Cu-RE (RE: rare earths) alloys could be improved by means of the partial substitution of Cu atoms by Al ones, as can be interred from the heterogeneous amorphous concept [1,2]. Instead of only one RE element, a solid solution of RE known as mischmetal (MM) was used....

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Bibliographic Details
Main Authors: Audebert, F, Rozenberg, S, Galano, M
Format: Conference item
Published: 2001
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Summary:The ductility of the amorphous Mg-Cu-RE (RE: rare earths) alloys could be improved by means of the partial substitution of Cu atoms by Al ones, as can be interred from the heterogeneous amorphous concept [1,2]. Instead of only one RE element, a solid solution of RE known as mischmetal (MM) was used. Rapidly quenched (RQ) samples (cooling rate > 10(3) K s(-1)) of Mg65AlxCu25-xMM10 (0 less than or equal to x less than or equal to 25 at.%) alloys were obtained in a splat cooling device. The structure and the crystallisation process were observed by means of X-ray diffraction (XRD) and differential scanning calorimetry (DSC). Fractographic analysis was carried out by scanning electron microscopy (SEM) on the fracture surface of samples broken by hand bending. With increase of the Al concentration, we observed that both the glass forming ability (GFA) and the amorphous pre-peak (a-pre-peak) in the XRD pattern decreased; meanwhile the crystallisation temperature increased. On the other hand, the ductility of the 10 at.% Al alloy was improved and a vein pattern was observed in the fracture surfaces. (C) 2001 Elsevier Science B.V. All rights reserved.