Simultaneous improvement in surface mechanical properties and corrosion resistance of biomedical ZK60 alloy by Zr and C co-implantation

• Published in: Vacuum 2023-02, Vol.208, p.111642, Article 111642
• Main Authors: Jia, Yongqiang, Duan, Weiwei, Ba, Zhixin, Yin, Kang, Sun, Tianyi, Wang, Yan
• Format: Article
• Language: English
• Subjects: Amorphous structure; Corrosion resistance; Magnesium alloy; Surface mechanical property; Surface strengthening; Zr and C co-Implantation
• ISSN: 0042-207X; 1879-2715
• DOI: 10.1016/j.vacuum.2022.111642

The effects of Zr + C co-implantation on surface mechanical properties and corrosion resistance of ZK60 Mg alloys were systematically investigated. The results illustrate that the ZK60 surface became more compact and smoother due to the surface restricting after Zr + C co-implantation, as well as the amorphous structure formed on its surface. The gradient implanted layer containing ZrO2 and ZrC was formed on its surface. Compared with the untreated, Zr-implanted and C-implanted samples, the Zr + C co-implanted layer improved its surface nano-hardness and modulus simultaneously, which is attributed to the irradiation hardening caused by dual Zr and C ion bombardment and the forming reinforced component (ZrO2, ZrC). The Zr + C co-implanted sample possessed the minimum corrosion tendency and the maximum polarization resistance (1.312 × 104 Ω cm2), and its corrosion current density (4.471 × 10−6 A cm−2) decreased by about an order of magnitude compare to the bare sample. The Zr + C co-implanted layer can protect the substrate withstands SBF solution during 168 h immersion confirmed by the minimum hydrogen evolution volume and milder corrosion morphology. In addition, Zr + C co-implantation improves the surface mechanical properties and corrosion resistance of ZK60 alloy simultaneously, which is a promising technique to expedite potential clinical applications of biomedical magnesium alloys. •The Zr and C atoms were introduced into the ZK60 magnesium surface by ion implantation.•A gradient, amorphous, ZrO2 and ZrC contained layer was formed on the ZK60 magnesium surface after Zr + C co-implantation.•The Zr + C co-implanted layer improved its surface mechanical properties due to the irradiation hardening and the forming reinforced component.•The Zr + C co-implanted layer also significantly improved the corrosion resistance of ZK60 in SBF.