Effect of Al on the Microstructure and Mechanical Properties of Mg-Sn-Ca-Mn Wrought Alloy

Mg-Sn-Ca-Mn-xAl (x = 0,1.5 wt%) alloys with ultra-fine recrystallized grains were prepared by conventional extrusion (400 degrees C, 0.5 mm/s). Effects of aluminum (Al) on mechanical properties and microstructure of the Mg-1Sn-1Ca-0.5Mn (wt%) alloy were systematically investigated. By the addition of 1.5 wt% Al, the yield strength of the as-extruded alloy significantly increased from 183 to 237 MPa. The as-cast alloys show a dendritic structure consists of alpha-Mg, (Mg, Al)(2)Ca, and CaMgSn phases. The as-extruded Mg-1Sn-1Ca-0.5Mn-1.5Al alloys exhibit a bimodal grain structure composed of dynamic recrystallized (DRXed) fine grains and coarse unDRXed grains. Compared with Al free alloy, a lot of nano-scale planar Al2Ca and rectangle shape Al8Mn5 precipitated in the as-extruded alloy with 1.5 wt% Al. Meanwhile, the addition of Al significantly strengthened alloys' fiber texture with < 10-10 >//ED. Graphic Abstract

Automated summary

The influence of aluminum on the mechanical properties and microstructure of Mg-Sn-Ca-Mn alloys was systematically investigated, and the addition of 1.5 wt% Al significantly increased the yield strength of the alloy. The extruded alloy exhibited a bimodal grain structure with dynamic recrystallized fine grains and coarse unrecrystallized grains. Additionally, the alloy with 1.5 wt% Al showed a significant enhancement in fiber texture.