|About this Abstract
||2016 TMS Annual Meeting & Exhibition
||Phase Transformations and Microstructural Evolution
||Carbide Evolution during Quenching and Partitioning of Steel Studied by Mössbauer Spectroscopy
||Dean Pierce, Dan Coughlin, Amy Clarke, Don Williamson, Jonathan Poplawsky, Kester Clarke, John Speer, David Matlock, Emmanuel De Moor
|On-Site Speaker (Planned)
Quenching and partitioning (Q&P) produces steel microstructures comprised primarily of martensite and austenite that exhibit promising mechanical properties. Understanding reactions that compete for the available carbon, such as carbide formation, is crucial for alloy design, processing, and achieving austenite enrichment and retention during Q&P processing. Mössbauer spectroscopy, transmission electron microscopy and atom probe tomography were used to quantify and characterize carbide formation in a 0.38C-1.54Mn-1.48Si wt. pct. steel after Q&P. The results indicate that η-carbide and cementite formed during Q&P processing and compete with carbon partitioning for the available carbon. Carbide formation consumed a significant percentage of the total carbon in this steel, which likely contributes to lower retained austenite fractions. Q&P processing parameters were optimized to minimize carbide formation and enhance carbon partitioning to austenite, retained austenite fractions and ductility. The findings of this work will allow processing optimization of Q&P treatments.
||Planned: A print-only volume