The Development of Dual-Phase Fe-Based Metallic Glasses and Composites with Optimized Mechanical and Magnetic Properties
DescriptionFe-based metallic glasses (MGs) are an important engineering material because of their superior soft magnetic properties. As compared to the traditional soft magnetic crystalline alloys, such as Fe-Si, soft magnetic Fe-based metallic glasses possess higher electric resistance and lower coercive force, thereby leading to extremely low energy loss when they are used for making the next generation of transformer cores. In addition, Fe-based metallic glasses have extraordinary strengths (2-4 GPa) and superior wear resistance. In view of such combination of structural and functional properties of the Fe-based metallic glasses, the central governments worldwide have recently made tremendous investments in the production of the soft magnetic metallic glasses. However, high performing Fe-based metallic glasses are generally brittle at the ambient condition because of a trade-off between magnetization saturation and plasticity. At the current time, this becomes the main roadblock that hurdles their industrial applications. Based on our previous research on metallic glasses, we herein propose several strategies in this proposal to mitigate the room-temperature brittleness in the soft-magnetic metallic glasses without sacrificing their magnetization saturation. These include the carefully selected chemical composition, which leads to a dual-phase amorphous structure, and the use of the recently developed processing methods which enable us to control the rejuvenation and relaxation of metallic glasses over an extended range that is impossible to achieve with the traditional rapid cooling method. In addition, we also design multi-scale experiments to elucidate the mechanisms underlying the brittlenessto-plasticity transition in our dual-phase Fe-based metallic glasses. Once funded, the outcome of our project is expected (1) to help people understand the origin of plasticity in the dual-phase metallic glasses, (2) to provide protocols that can improve the quality of soft-magnetic metallic glasses, and (3) to promote the use of metallic glasses in the energy industries that play a pivotal role to the societal and economic growth in mainland China and Hong Kong.
|Effective start/end date||1/01/19 → …|