Paper Title:
Microstructural Evolution of Rheo-Diecast AZ91D Magnesium Alloy with Gadolinium Addition
  Abstract

The rheo-diecasting (RDC) process, a novel semi-solid processing technology, was used to produce cast components with high integrity, fine and uniform microstructure, and therefore enhanced performance. AZ91D samples with 1-3 mass%Gd were solidified by RDC process. It was found that under intensive forced convection, the primary α-Mg phase produced inside the twin-screw slurry maker had fine particle size, spherical morphology and uniform distribution throughout the samples. Microstructure observations showed that Gd addition resulted in the formation of Al2Gd which dispersed in the α-Mg matrix. The size and amount of β-Mg17Al12 phase was reduced and its continuity was broken, which was the main reason for improving mechanical properties of the AZ91D alloy at high temperatures. The amount of Al2Gd particles increased with increasing Gd addition. From EPMA quantitative analysis, almost all Gd reacted with Al, leading to the low concentration of Gd in the α-Mg matrix. The Vickers hardness increased monotonously from HV=50.4 to HV=67.3 with increasing amount of Gd. This improvement was attributed to the consummation of aluminum in melt by precipitation of the Al2Gd phases.

  Info
Periodical
Materials Science Forum (Volumes 654-656)
Main Theme
Edited by
Jian-Feng Nie and Allan Morton
Pages
667-670
DOI
10.4028/www.scientific.net/MSF.654-656.667
Citation
J. L. Zhang, X. T. Wang, Y. He, Y. L. Wang, "Microstructural Evolution of Rheo-Diecast AZ91D Magnesium Alloy with Gadolinium Addition", Materials Science Forum, Vols. 654-656, pp. 667-670, 2010
Online since
June 2010
Export
Price
$32.00
Share

In order to see related information, you need to Login.

In order to see related information, you need to Login.

Authors: Xiang Guo Liu, Xiao Dong Peng, Wei Dong Xie, Qun Yi Wei
Abstract:In this paper, effects of strontium on Mg alloys and preparation technology of Mg-Sr and Mg-Sr-Al master alloys were summarized respectively....
31
Authors: Ming Bo Yang, Fu Sheng Pan, Jing Zhang, Jin Zhang
Abstract:The current status of research and application in the AZ(Mg-Al-Zn), AS(Mg-Al-Si), AE(Mg-Al-RE), AX(Mg-Al-Ca), ACM or MRI(Mg-Al-Ca-RE)and...
923
Authors: Jeong Min Kim, Bong Koo Park, Joong Hwan Jun, Ki Tae Kim, Woon Jae Jung
Abstract:Small amounts of minor alloying elements such as RE and Sr were added to Mg- 8wt%Al-5wt%Zn (AZ91D+4%Zn), and their effects on the...
374
Authors: E.P. Masuku, Gonasagren Govender, L. Ivanchev, Heinrich Möller
Abstract:Rheocasting of alloys A206 and A201 was investigated in this study. Conical bars with different silver contents were produced using CSIR...
151
Authors: Xiao Ping Luo, Lan Ting Xia, Ming Gang Zhang
Abstract:The effect of Cd and Sb addition on the microstructural and mechanical properties of as-cast AZ31 alloys was investigated and compared. The...
197