Hits:

Indexed by:期刊论文

Date of Publication:2012-05-01

Journal:JOURNAL OF RARE EARTHS

Included Journals:SCIE、EI、ISTIC

Volume:30

Issue:5

Page Number:492-496

ISSN No.:1002-0721

Key Words:Mg-Li-Al alloy; Nd; grain refinement; microstructure; mechanical properties; rare earths

Abstract:Effects of Nd on microstructure and mechanical properties of as-cast Mg-8Li-3Al alloy were investigated by OM, X-ray diffraction (XRD), EPMA, scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The results showed that the dendrites sizes of alpha phase were decreased by the Nd addition. When the amount of addition Nd was 1.6 wt.%, the alloy with the smallest alpha phase was obtained. The refining mechanism mainly owed to the increasing constitutional supercooling at the solidification front. Furthermore, the compound Al2Nd generated by the reaction of Al and Nd, which distributed at the phase boundary and inside beta phase, could also restrain the growth of alpha phase. Nd could improve the tensile strength and elongation of Mg-8Li-3Al alloy, however, excessive Al2Nd might also become crack source and decrease the elongation.