Microstructure and mechanical properties of SiC particles reinforced Mg–8Al–1Sn magnesium matrix composites fabricated by powder metallurgy

Abstract

The new type of Mg–8Al–1Sn (AT81) magnesium matrix composites reinforced with different volume fractions (5, 10, 15, 20, 25 and 30 vol.-%) of SiC particles (average size of 10 μm) was fabricated by powder metallurgy. With the increasing volume fraction of SiC particles (SiC_p), the particles gradually show more homogeneous distribution. Compared with the AT81 alloy, the yield strength (YS) and ultimate compressive strength of the SiC_p/AT81 composites are improved simultaneously. With the increasing SiC_p from 0 to 30 vol.-%, the YS and ultimate compressive strength increase from 69 to 239 MPa and 286 to 385 MPa respectively, while the corresponding fracture strain (ε) decreases from 19·3 to 4·8%. The improvement of the YS and ultimate compressive strength of the SiC_p/AT81 composites benefits from the more homogeneous microstructure due to the increase in the SiC particles.

Keywords:

• Magnesium
• Powder metallurgy
• Microstructure
• Mechanical properties

Acknowledgements

Financial supports from the Natural Science Foundation of China (NSFC) (Grant No. 51271086 and No. 51301074) and The Doctoral Fund of Ministry of Education of China (Grant No. 20120061110031) are greatly acknowledged. Partial financial supports come from The Natural Science Foundation of Jilin Province (Grant No. 201115010) and The National Training Programs of Innovation and Entrepreneurship for Undergraduates (Grant No. 2013A43127).