Research microstructure and mechanical properties of AZ31 magnesium alloy by semisolid extruding with electromagnetic stirring process

Qiang Li, Weifang Key Lab of Light Weight Material Manufacturing and Processing, Shandong, China; Weifang University of Science and Technology, Jinguang St., Shouguang, Shandong, China

Dongbai Xie, Weifang Key Lab of Light Weight Material Manufacturing and Processing, Shandong, China; Weifang University of Science and Technology, Jinguang St., Shouguang, Shandong, China

Hui Guo, Weifang Key Lab of Light Weight Material Manufacturing and Processing, Shandong, China; Weifang University of Science and Technology, Jinguang St., Shouguang, Shandong, China

Abstract
To improve AZ31 magnesium (Mg) alloy plasticity, semisolid extruding with electromagnetic stirring process was adopted, and then the mechanical properties and microstructure were studied. The melting temperature was 730℃, and the preheat temperature of the die was set as 300℃, and electromagnetic stirring parameters were 6Hz and 150A with the stirring time 45s, while the rheological extrusion force was 3000KN, the extruding speed was 2mm/s, extruding time was 35s and the extrusion ratio is 10:1. The results show that tensile strength and grain size of AZ31 Mg alloy without rheological extrusion were 174MPa and 124µm, and there were some twins appeared in grains due to the electro-magnetic stirring treatment. With extrusion process, the grain size was refined to 4.91µm, and recrystallization was happened. In addition the tensile strength and the elongation rose up to 206 MPa and 18.35%, respectively, which indicated that the semi-solid processing combined electro-magnetic stirring with extruding technology could improve the tensile and elongation of AZ31 Mg alloy greatly.

Keywords
Magnesium AZ31 alloy; Semisolid extruding; Electromagnetic stirring, mechanical properties

Cite this paper
Qiang Li, Dongbai Xie, Hui Guo, Research microstructure and mechanical properties of AZ31 magnesium alloy by semisolid extruding with electromagnetic stirring process , SCIREA Journal of Materials. Volume 7, Issue 3, June 2022 | PP. 46-57. 10.54647/materials43193

References

[ 1 ]	Harooni, M., et al., Pore formation mechanism and its mitigation in laser welding of AZ31B magnesium alloy in lap joint configuration. Materials & Design, 2014. 58: p. 265-276.
[ 2 ]	Chang, Z., et al., Semisolid rheoforming of magnesium alloys: A review. Materials & Design, 2020. 195: p. 108990.
[ 3 ]	Chu, C.-l., et al., Evolution and distribution of Al 2 Sm phase in as-extruded AZ61– x Sm magnesium alloys during semi-solid isothermal heat-treatment. Transactions of Nonferrous Metals Society of China, 2018. 28(7): p. 1311-1320.
[ 4 ]	Czerwinski, F., The processing phenomena of semisolid Mg–9% Al–1% Zn alloy at ultra high contents of the unmelted phase. Materials Science and Engineering: A, 2005. 392(1-2): p. 51-61.
[ 5 ]	Nami, B., et al., Effect of Ca, RE elements and semi-solid processing on the microstructure and creep properties of AZ91 alloy. Materials Science and Engineering: A, 2011. 528(3): p. 1261-1267.
[ 6 ]	Feng, J., et al., Improved microstructures of AZ31 magnesium alloy by semi-solid extrusion. Materials Science and Engineering: A, 2021. 800: p. 140204.
[ 7 ]	Patel, H.A., et al., Cyclic deformation and twinning in a semi-solid processed AZ91D magnesium alloy. Materials Science and Engineering: A, 2010. 528(1): p. 208-219.
[ 8 ]	Xing, B., et al., Microstructure control of AZ31 alloy by self-inoculation method for semisolid rheocasting. Transactions of Nonferrous Metals Society of China, 2013. 23(3): p. 567-575.
[ 9 ]	Kleiner, S., et al., Microstructure and mechanical properties of squeeze cast and semi-solid cast Mg–Al alloys. Journal of Light Metals, 2002. 2(4): p. 277-280.
[ 10 ]	Zhang, X., et al., Texture evolution in semi-solid partial remelting and its effect on the microstructure of magnesium alloy. Materials Letters, 2019. 237: p. 141-144.
[ 11 ]	Chen, G., et al., Controlling liquid segregation of semi-solid AZ80 magnesium alloy by back pressure thixoextruding. Journal of Materials Processing Technology, 2018. 259: p. 88-95.
[ 12 ]	Tu Y., et al., Phases and Microstructure of As-cast AZ31 Magnesium Alloy. Foundry, 2006. 55: p.509-512. (in Chinese).