Abstract
The effect of Si addition on the initial deformation mechanism of Fe–30Mn–9Al–0.9C–0.5Mo cast lightweight steel has been investigated. Atomic-scale analysis by three-dimensional atom-probe tomography confirmed that Si addition accelerates the formation kinetics of the κ-carbide, and increases remarkably the partitioning coefficient of carbon by more than 2 times. Promotion of C partitioning into κ-carbides by Si addition leads to deformation localization in an aged state. This is attributed not only to the increase of the κ-carbide size associated with higher coherency strain, but also to higher frequency of Al-C bonding formation. First-principles calculations indicated that the energy required for a/2<110> shearing of κ-carbide in the aged 1%-Si steel is higher (561 mJ/m2) than that in the aged Si-free steel (494 mJ/m2). Therefore, Si addition leads to a significant energy difference for shearing and results in different shear bands formation. The operative deformation mechanism can be calculated for this alloy system as a function of precipitates volume fraction and size. It was determined that deformation proceeds primarily by κ-carbide shearing as long as the radius of κ-carbides is smaller than 13.4 nm.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
