| About this Abstract |
| Meeting |
2024 TMS Annual Meeting & Exhibition
|
| Symposium
|
Advanced Soft Magnets and Magnetocaloric Materials: An FMD Symposium in Honor of Victorino Franco
|
| Presentation Title |
Evaluation of Martensite Transformation Temperatures Using Magnetometry |
| Author(s) |
Nicholas J. Jones, Paul K Lambert, Jin Hyeong Yoo, Suok Min Na, Charles R Fisher |
| On-Site Speaker (Planned) |
Nicholas J. Jones |
| Abstract Scope |
Martensite start and finish temperatures are two critical parameters needed to define the processing variables for steels. Magnetization measurements have been used herein as a method to determine these structural phase transformation temperatures, leveraging knowledge from both the soft magnetics and magnetocaloric communities. Eight compositions of steel having published martensite start temperatures ranging from -130 °C to +30 °C were synthesized via vacuum arc melting. After a high-temperature homogenization heat treatment, samples were extracted and room-temperature magnetic hysteresis loops were measured before and after a temperature cycle to cryogenic temperatures under constant applied field. Samples showed pronounced increases in magnetization as temperature decreased due to the irreversible martensitic transformation, and eventually magnetization plateaued below the sample’s martensite finish temperature. The choice of applied magnetic field strength will be discussed, along with a comparison between individual magnetization versus temperature curves and hysteresis loops measured as a function of temperature. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Characterization, Magnetic Materials, Iron and Steel |