Date of Award

2021

Document Type

Open Access Master's Thesis

Degree Name

Master of Science in Materials Science and Engineering (MS)

Administrative Home Department

Department of Materials Science and Engineering

Advisor 1

Jaroslaw Drelich

Committee Member 1

Stephen Kampe

Committee Member 2

Dan Seguin

Abstract

The development of magnesium bioresorbable implants has become increasingly popular due to the increased need for temporary implants and magnesium’s excellent biocompatibility and suitable elastic modulus. Even though magnesium is an excellent candidate, when alloyed with other metals magnesium’s corrosion rate becomes too rapid for bioresorbable medical applications. The investigation into novel processing techniques to control the formation of precipitates to improve mechanical strength and ductility as well as corrosion rates has become of interest. This work investigates the combination of two nonequilibrium processing techniques, rapid solidification (RS) and equal channel angular pressing (ECAP), and the effects it has on the strength, ductility, and corrosion properties of two Mg-Zn-Ca-Mn alloys: Mg-1.2Zn-0.8Ca-0.2Mn and Mg-1.8Zn-0.8Ca-0.2Mn. In the course of this study, it was found that the formulated alloys possessed flaws from processing responsible for a premature mechanical failure of samples. As the result, alloys’ ductility improvements from processing could not be explored. Additionally, ECAP processing caused the dynamic precipitation of nano-size Ca­2Mg6Zn3 precipitates which contributed to an increase in strength from the RS consolidated state after ECAP was performed. Corrosion testing also determined that ECAP caused an increase in corrosion rate of formulated alloys.

Creative Commons License

Creative Commons Attribution 4.0 License
This work is licensed under a Creative Commons Attribution 4.0 License.

Additional Files
00 Publishing Agreement 9-2021.pdf (77 kB)
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