About this Abstract |
Meeting |
MS&T24: Materials Science & Technology
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Symposium
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Controlled Synthesis, Processing, and Applications of Structural and Functional Nanomaterials
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Presentation Title |
Advancements in Synthesis and Characterization of High-Purity Mn4C for Thermomagnetic Energy Devices |
Author(s) |
Baochao Zhang, Tianhong Zhou, Xing Zheng, Youngwoon Song, Pingzhan Si, Oi Lun Li, Chul-Jin Choi, Jihoon Park |
On-Site Speaker (Planned) |
Jihoon Park |
Abstract Scope |
This study focuses on the anomalous thermomagnetic properties of Mn4C, an intermetallic compound, with a positive temperature coefficient of magnetization (α) of approximately 0.0072 Am2/kg·K, making it attractive for controlling magnetization thermodynamics. Over half a century of research has led to the development of efficient methods for synthesizing high-purity Mn4C due to its instability at room temperature compared to Mn4N. A novel synthesis approach involving arc-melting, homogenization, and water-quenching steps was devised to overcome previous limitations in batch size and purity. Optimization studies on stoichiometry and homogenization parameters resulted in highly pure Mn4C ingots, particularly by homogenizing Mn4.7C alloys at 1100 ℃ for 5 hours followed by water quenching. The resulting sample exhibited a Néel temperature of ~950 K, saturation magnetization of 8.4 Am2/kg, and a positive α of 0.0113 Am2/kg·K. This work demonstrates the potential of high-purity Mn4C for energy devices requiring stable magnetization over a broad temperature range. |