About this Abstract |
Meeting |
Materials Science & Technology 2019
|
Symposium
|
Retained Austenite for High and Ultrahigh Strength Steels
|
Presentation Title |
Carbon Partitioning between Ferrite and Austenite in Medium-Mn Steel and its Impact on Mechanical Properties |
Author(s) |
Yan Ma, Binhan Sun, Wenwen Song, Wolfgang Bleck |
On-Site Speaker (Planned) |
Wolfgang Bleck |
Abstract Scope |
In the present work, the influence of cooling conditions, namely water-quenching (WQ) and air-cooling (AC), on medium-Mn steel Fe-12Mn-3Al-0.05C (wt%) was investigated. The synchrotron XRD experiments showed that the cooling conditions after intercritical annealing had a neglected effect on the amount of retained austenite. The atom probe tomography investigation showed that there was no obvious carbon enrichment at phase boundaries of ferrite and austenite in the WQ specimen, while carbon atoms strongly enriched at phase boundaries in the AC specimen. Consequently, the WQ specimen exhibited continuous yielding behavior, while AC specimen manifested discontinuous yielding behavior. The yield strength increased by ~ 80 MPa by AC. At the same time, the uniform elongation of the AC specimen was ~ 5% higher than that of the WQ specimen. The results indicate that cooling conditions have a strong influence on carbon redistribution, the mechanical stability of retained austenite and strain-hardening behavior. |