CAREER: Towards High Strength Corrosion-Resistant Magnesium Alloys

University Of Akron, Akron OH

Investigators

Abstract

In order to meet current technological, socio-economic and environmental challenges, the need for lightweight, high strength and corrosion resistant alloys is increasing continuously. Magnesium, the third most abundant metal, is the lightest of all structural metals and therefore has attracted significant attention for a number of industries including aerospace, automotive, and infrastructure applications. Magnesium alloys also possess excellent biocompatibility and support bone growth, and thus these alloys are also considered candidate materials for biomedical applications. The use of magnesium alloys in these applications, however, is limited but their poor resistance to environmental degradation and low strength. The ability to mitigate the corrosion of magnesium alloys while simultaneously increasing the strength could revolutionize the automotive and aerospace industries, as well as the field of biomaterials. This Faculty Early Career Development Program (CAREER) award supports research to understand the fundamental mechanisms of both strength and corrosion resistance in magnesium alloys, with the goal of providing unprecedented control over the properties and making it possible to tailor these materials for specific technical applications. The work also incorporates far-reaching educational and outreach objectives to inspire students in grades K-12 to purse education in STEM disciplines; to recruit, retain and support outstanding and diverse student groups at undergraduate and graduate levels; and to provide students the opportunities for active learning, mentorship, and scholarship related to this research areas. The outreach programs include research opportunities to high school students, working with the high school teachers to stimulate interests in STEM fields among young students and broaden participation of underrepresented groups. This research will contribute to the fundamental understanding of the properties of metastable nanocrystalline magnesium (Mg) alloys and the mechanisms that can enable high strength and corrosion resistant Mg alloys. Inspired by the phenomenon causing the "stainless" behavior in stainless steels, an innovative approach of improving mechanical strength and corrosion resistance of Mg alloys will be undertaken. The specific objectives of this research are to: 1) produce Mg alloys with a wide range of grain size, dispersion of intermetallics, and solid solubility of the alloying element; 2) study the influence of the nanocrystalline structure, the solid solubility of the metal alloying elements, and intermetallics on corrosion and mechanical properties; 3) identify the key mechanisms causing simultaneous improvement in corrosion and mechanical properties of magnesium alloys, and develop a theoretical framework for designing high strength corrosion resistant magnesium alloys. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.