Effect of Sc/Sm microalloying on microstructural and properties of Mg 2Zn-0.3Ca biodegradable alloy

The influences of Sc/Sm microalloying on microstructure, mechanical property, bio-corrosion behavior and biocompatibility of the as-cast Mg-2Zn-0.3Ca alloy have been investigated in the study. The results demonstrate that Sc microalloying obviously refines the grain of the Mg-2Zn-0.3Ca alloy, leading to the improvement of yield strength (82 MPa). While the coarse and discontinuous eutectic phases (alpha-Mg +Ca2Mg6Zn3) accelerate the galvanic corrosion near the grain boundary. Sm microalloying promotes the formation of finely dispersed particles (Ca2Mg6Zn3-Sm) of the Mg-2Zn-0.3Ca alloy, reducing the electrode potential difference of the second phase and matrix. The Mg-2Zn-0.3Ca-0.4Sm alloy has the most moderate corrosion and compact protective layer in the three alloys, exhibiting excellent corrosion resistance (Pw = 1.26 mm.y(-1)) in vitro. The Mg-2Zn-0.3Ca-0.4Sc/Sm alloys are non-cytotoxic and promote cell proliferation. (C) 2022 Elsevier B.V. All rights reserved.

Automated summary

The influences of Sc/Sm microalloying on microstructure, mechanical property, bio-corrosion behavior and biocompatibility of the as-cast Mg-2Zn-0.3Ca alloy have been investigated. Sc microalloying refines the grain and improves the yield strength, while Sm microalloying promotes the formation of dispersed particles. Mg-2Zn-0.3Ca-0.4Sm alloy exhibits the best corrosion resistance and protective layer, and is non-cytotoxic and promotes cell proliferation.