Please use this identifier to cite or link to this item:
Type: Artigo
Title: Compositional analysis on the reverted austenite and tempered martensite in a Ti-stabilized supermartensitic stainless steel : segregation, partitioning and carbide precipitation
Author: Escobar, J.D.
Poplawsky, J.D.
Faria, G.A.
Rodriguez, J.
Oliveira, J.P.
Salvador, C.A.F.
Mei, P.R.
Babu, S.S.
Ramirez, A.J.
Abstract: Controlling the amount of reverted austenite at room temperature allows for tailoring of mechanical properties in supermartensitic stainless steels. The austenite reversion and stabilization occurs during inter-critical tempering through partitioning of austenite-stabilizing elements. The degree of partitioning greatly depends on the reversion temperature, which dictates the local equilibrium conditions. Atom probe tomography and energy dispersive spectroscopy in transmission electron microscopy were used to study the austenite reversion mechanism in terms of the elemental distribution of austenite-stabilizing, ferrite-stabilizing and carbide forming elements. Synchrotron X-ray diffraction confirmed that the austenite equilibrium phase fraction was reached after 2.5 h of isothermal reversion at 625 °C, allowing for direct comparison with thermodynamic and kinetic calculations. However, such soaking time was not enough to produce compositional homogenization in the reverted austenite. The austenite reversion and stabilization mechanism was related mainly to strong partitioning of Ni. Negligible partitioning of Cr, Mo, Si and Ti were observed. Instead, these elements were strongly segregated at the reverted austenite/martensite interfaces. Carbon and Ti played a secondary role in the austenite stabilization through the precipitation of nano-sized Ti (C,N) with partial substitution of Ti by Mo. Virtually carbon-free austenite and martensite were observed away from the interfaces and precipitates
Subject: Tomografia
Country: Reino Unido
Editor: Elsevier
Rights: Aberto
Identifier DOI: 10.1016/j.matdes.2017.11.055
Date Issue: 2018
Appears in Collections:FEM - Artigos e Outros Documentos

Files in This Item:
File Description SizeFormat 
2-s2.0-85035804707.pdf3.08 MBAdobe PDFView/Open

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.