|About this Abstract
||2018 TMS Annual Meeting & Exhibition
||Phase Transformations and Microstructural Evolution
||Kinetics Analysis of Tempering, Inter-critical Annealing and Austenitization of Supermartensitic Stainless Steels
||Frank Niessen, Matteo Villa, Frédéric Danoix, John Hald, Marcel Adrianus Johannes Somers
|On-Site Speaker (Planned)
Supermartensitic stainless steels are lath martensitic steels with ultra-low interstitial content and are based on the Fe-Cr-Ni system. The alloy grade is popular as a low-cost alternative to highly alloyed duplex stainless steels for oil and gas pipeline applications. The strength and toughness of the initially martensitic microstructure is based on formation of reversed austenite from lath martensite during inter-critical annealing. The homogeneity after austenitization, residual stresses from martensite formation and tempering reactions of martensite upon reheating affect the conditions for formation and stabilization of austenite. The kinetics and mechanisms of these preceding reactions and the formation of reversed austenite were measured experimentally by correlative use of synchrotron diffraction, atom probe tomography and Transmission Kikuchi diffraction, and were modeled with thermodynamics and kinetics modeling. The distribution of the interstitial elements and Ni significantly affect the phase transformation kinetics in supermartensitic stainless steels.
||Planned: Supplemental Proceedings volume