Effect of Ca content on microstructure and strength of as-extruded Mg-1.0Al-xCa alloy

Abstract

In this work, the effects of Ca content and extrusion temperature on the microstructures and mechanical properties of Mg–1Al–xCa alloys have been investigated. For Mg–1.0Al–0.4Ca (wt-%, AX10) dilute alloy, decreasing extrusion temperature from 290°C to 260°C can inhibit the dynamic recrystallisation (DRX) process, and the yield strength (YS) is also increased from ∼266 ± 6 MPa to ∼309 ± 3 MPa. When increasing the Ca content, Mg–1.0Al–0.8Ca (wt-%, AX11), a higher density of the Al₂Ca phase is dispersed at the grain boundaries, which can further restrict the growth of DRXed grains, only ∼1.0 µm. Consequently, the higher YS of ∼330 ± 5 MPa can be obtained. The relevant results can shed light on designing other high-strength and low-alloyed Mg wrought alloys.

KEYWORDS:

• Mg alloy
• alloying
• mechanical property
• strengthening
• second phases

Acknowledgements

Special thanks are due to Dr Na Xiao in Analytical and Testing Center of Northeastern University for the assistance with EBSD analysis.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work is supported by National Key Research and Development Program of China [Grant Number 2021YFB3701002], National Natural Science Foundation of China [Grant Numbers U2167213, 51971053, 52271092], and Chongqing Science and Technology Commission (CSTB2022NSCQ-MSX0891). H.C. Pan acknowledges the financial assistance from Young Elite Scientists Sponsorship Program by China Association for Science and Technology [Grant Number 2019-2021QNRC001-003], and the fund from the Fundamental Research Funds for the Central Universities [Grant Number N2202020].