Laves phase precipitation and its transformation kinetics in the ferritic stainless steel type AISI 441
Loading...
Date
Authors
Sello, M.P.
Stumpf, Waldo E.
Journal Title
Journal ISSN
Volume Title
Publisher
Elsevier
Abstract
Electrolytic extraction followed by XRD analysis of precipitates after isothermal annealing of an AISI 441
ferritic stainless steel between 600 and 850 ◦C produced the time–temperature–precipitation (TTP) diagram
for the Fe2Nb-Laves phase. The TTP diagram shows two classical C noses, the first one between 750
and 825 ◦C and the second one, estimated to be close to 650–675 ◦C. TEM analyses show two independent
nucleation mechanisms, i.e. at about 600 ◦C nucleation takes place on dislocations but above 750 ◦C,
grain boundary nucleation is dominant. The measured solvus temperature of 875 ◦C for Fe2Nb in this
steel is 50 ◦C higher than predicted by Thermo-Calc®. Kinetic modelling at 800 ◦C agreed well with the
experimental results for a surface energy of 0.435 J m−2 and an initial particle center-to-center separation
distance on grain boundaries of about 0.2 m.
Description
Keywords
Laves phase (Fe2Nb), Johnson–Mehl–Avrami–Kolmogorov (JMAK), Transformation kinetics, Laves phase precipitation, Ferritic stainless steel type AISI 441, Time–temperature–precipitation (TTP)
Sustainable Development Goals
Citation
Sello, MP & Stumpf, WE 2011, 'Laves phase precipitation and its transformation kinetics in the ferritic stainless steel type AISI 441', Materials Science and Engineering A-Structural Materials Properties Microstructure and Processing, vol. 528, no. 3, pp. 1840-1847.