About this Abstract |
| Meeting |
MS&T25: Materials Science & Technology
|
| Symposium
|
High-Temperature Corrosion and Degradation of Materials
|
| Presentation Title |
Selective Oxidation of Sm in SmCo-based Magnets: Kinetics and Mechanisms |
| Author(s) |
Mitchell Harvey, Courtney Young, Mario Caccia |
| On-Site Speaker (Planned) |
Mitchell Harvey |
| Abstract Scope |
Samarium-cobalt (SmCo) permanent magnets are used in key industrial and defense applications due to their improved performance at elevated temperatures compared to the more common NdFeB magnets. At these elevated temperatures, internal oxidation of the Sm2Co17 phase in SmCo magnets leads to a reduction in their magnetic properties. Internal oxidation studies in literature focus on commercial SmCo magnets which contain variable quantities of Fe, Cu, and Zr added to improve the properties of the magnets. The internal oxidation of SmCo magnets in the presence of these elements is a strong function of the oxygen partial pressure as multiple internal oxidation reactions can occur. In order to gain a fundamental understanding of the internal oxidation of Sm in Sm2Co17, coupons of nominally pure Sm2Co17 were oxidized using a Rhines pack with Co/CoO powder as the pO2 buffer. Oxidation kinetics and rate limiting mechanisms were investigated using weight measurements and cross-sectional analysis. |