Exceptional Strengthening of Biodegradable Mg-Zn-Ca Alloys through High Pressure Torsion and Subsequent Heat Treatment.

Materials
Jelena HorkyMichael J Zehetbauer

Abstract

In this study, two biodegradable Mg-Zn-Ca alloys with alloy content of less than 1 wt % were strengthened via high pressure torsion (HPT). A subsequent heat treatment at temperatures of around 0.45 Tm led to an additional, sometimes even larger increase in both hardness and tensile strength. A hardness of more than 110 HV and tensile strength of more than 300 MPa were achieved in Mg-0.2Zn-0.5Ca by this procedure. Microstructural analyses were conducted by scanning and transmission electron microscopy (SEM and TEM, respectively) and atom probe tomography (APT) to reveal the origin of this strength increase. They indicated a grain size in the sub-micron range, Ca-rich precipitates, and segregation of the alloying elements at the grain boundaries after HPT-processing. While the grain size and segregation remained mostly unchanged during the heat treatment, the size and density of the precipitates increased slightly. However, estimates with an Orowan-type equation showed that precipitation hardening cannot account for the strength increase observed. Instead, the high concentration of vacancies after HPT-processing is thought to lead to the formation of vacancy agglomerates and dislocation loops in the basal plane, where they repres...Continue Reading

References

Oct 26, 2005·Biomaterials·Mark P StaigerGeorge Dias
Jul 5, 2006·Nature Materials·E MaX L Wu
Feb 23, 2010·Acta Biomaterialia·Frank Witte
Sep 18, 2013·Biomedizinische Technik. Biomedical Engineering·K HaslingerB Mingler
Jan 25, 2014·Journal of Biomedical Materials Research. Part B, Applied Biomaterials·Jemimah WalkerGeorge J Dias
Jul 19, 2014·Acta Biomaterialia·Yongjun ChenJag Sankar
Dec 17, 2014·Journal of the Mechanical Behavior of Biomedical Materials·Stanislava Fintová, Ludvík Kunz

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Citations

Apr 12, 2020·Materials·Darja Steiner PetrovičDmytro Orlov
Sep 29, 2020·Scientific Reports·Md Ershadul AlamIrene J Beyerlein
Aug 22, 2021·Journal of Biomedical Materials Research. Part a·Anuradha JanaVamsi Krishna Balla

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Methods Mentioned

BETA
Scanning electron microscopy
transmission electron microscopy
optical microscopy
thermal treatment
thermal treatments

Software Mentioned

IVAS

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