In:
Materials Science Forum, Trans Tech Publications, Ltd., Vol. 817 ( 2015-4), p. 399-405
Abstract:
The effects of the homogenization conditions on the microstructure of Al-Zn-Mg-Cu-Zr-0.5Er alloy were investigated by differential scanning calorimetry (DSC), optical microscopy (OM), scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), and X-ray diffraction (XRD). The results showed that a lot of coarse phases existed in as-cast Al-Zn-Mg-Cu-Zr-0.5Er alloy. The dissolvable phases at grain boundary consisted of Mg 32 (Al, Zn) 49 . The residual phases dissolved into the matrix gradually during homogenization with increasing temperature and prolonging holding time. When the temperature increased to 465°C, and time prolongs to 24h, the main phase disappeared except the Fe and Er enriched phase, as a result of its high melting temperature. Taking into account the precipitation of Al 3 Er, we used a two-step homogenization .Hence, the optimum parameters of homogenization were 400 °C for 4 h and 465 °C for 24 h, which are good for the presence of coherent, elastically hard and nanosized Al 3 (Er, Zr) particles and the dissolvable coarse phases .
Type of Medium:
Online Resource
ISSN:
1662-9752
DOI:
10.4028/www.scientific.net/MSF.817
DOI:
10.4028/www.scientific.net/MSF.817.399
Language:
Unknown
Publisher:
Trans Tech Publications, Ltd.
Publication Date:
2015
detail.hit.zdb_id:
2047372-2
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