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Effect of ceramic nanoparticle reinforcements on the quasistatic and dynamic mechanical properties of magnesium-based metal matrix composites

Published online by Cambridge University Press:  26 March 2013

Jianghua Shen ,
Weihua Yin ,
Qiuming Wei ,
Yulong Li ,
Jinling Liu  and
Linan An
Jianghua Shen
Affiliation:
Department of Mechanical Engineering and Engineering Science, The University of North Carolina at Charlotte, Charlotte, North Carolina 28223-0001
Weihua Yin
Affiliation:
Department of Mechanical Engineering and Engineering Science, The University of North Carolina at Charlotte, Charlotte, North Carolina 28223-0001
Qiuming Wei*
Affiliation:
Department of Mechanical Engineering and Engineering Science, The University of North Carolina at Charlotte, Charlotte, North Carolina 28223-0001
Yulong Li
Affiliation:
Department of Aeronautical Structure Engineering, School of Aeronautics, Northwestern Polytechnical University, Xi’an, Shannxi, 710072, People’s Republic of China
Jinling Liu
Affiliation:
Advanced Materials Processing and Analysis Center, University of Central Florida, Orlando, Florida 32816
Linan An*
Affiliation:
Advanced Materials Processing and Analysis Center, University of Central Florida, Orlando, Florida 32816
*
a)Address all correspondence to these authors. e-mail: qwei@uncc.edu
b)e-mail: Linan.An@ucf.edu
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Abstract

We have investigated the microstructure, the quasistatic and high-rate mechanical properties of magnesium (Mg)-based metal-matrix composites (MMCs) reinforced with nanoparticles, also termed as metal-matrix nanocomposites (MMNCs), in this case reinforced with nanoparticles of β-phase silicon carbide (β-SiC) the volume fraction ranging from 5 to 15 vol%. The yield and the ultimate strength increase with reinforcement volume fraction up to 10 vol% nanoparticles. MMCs with micrometer-sized SiC particles have higher yield strength than their MMNC counterparts, whereas the ultimate strength shows the opposing trend, suggesting greater strain hardening in the MMNCs. Transmission electron microscopy shows that the average interparticle distance decreases with increasing SiC vol%. Recrystallization was reported as completed during sintering at 575 °C [R.D. Doherty et al., Mater. Sci. Eng. A, 238, 219 (1997)], but dislocations might be generated due to thermal expansion mismatch of Mg/SiC during cooling. The majority of Mg-grains below 20 nm remain around the nanoparticles. As such a reverse volume fraction effect takes place in 15 vol% nanoparticle-reinforced MMNCs, which off sets the strengthening advantage induced by the nanoparticles.

Keywords

metal matrix compositenanocompositemagnesiummicrostructuremechanical properties

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Articles
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Journal of Materials Research , Volume 28 , Issue 13: FOCUS ISSUE: Frontiers in Thin-Film Epitaxy and Nanostructured Materials , 14 July 2013 , pp. 1835 - 1852
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Copyright © Materials Research Society 2013 

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