| About this Abstract |
| Meeting |
MS&T22: Materials Science & Technology
|
| Symposium
|
Advances in Ferrous Metallurgy
|
| Presentation Title |
Evaluation of Martensite Transformation Temperatures Using Magnetometry |
| Author(s) |
Nicholas John Jones, Paul K. Lambert, Jin-Hyeong Yoo, Suok-Min Na, Charles R. Fisher |
| On-Site Speaker (Planned) |
Nicholas John 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. 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 irreversible martensitic transformation, and eventually magnetization plateaued below the sample’s martensite finish temperature. In addition to the measured martensite start and finish temperatures and general characterization of the samples, the choice of applied magnetic field strength will be discussed, to ensure that the transformation is being appropriately characterized. |