This file was created by the TYPO3 extension bib --- Timezone: CET Creation date: 2021-01-26 Creation time: 14-28-29 --- Number of references 1 article Koutsoukis:2011 Solid State Phenomena 2011 172-174 Part 1 493-498 Superaustenitic stainless steels exhibit excellent corrosion resistance, at a wide variety of exposure temperatures, especially in chloride containing environments, coupled with desirable mechanical properties. Previous studies have shown that these steels are prone to precipitation of secondary phases, such as sigma phase (sigma), chi phase (chi). Laves-phase, carbides, nitrides or secondary austenite, when exposed at elevated temperatures, directly affecting their mechanical properties and corrosion behaviour. A detailed study of the effect of isothermal ageing on the microstructure of S32654 (Fe-24Cr-21Ni-7Mo-0.5N-0.013C) and S31254 (Fe-20Cr-18Ni-6Mo-0.2N-0.012C) superaustenitic stainless steels was carried out. Samples were aged within the temperature range of 650 degrees C to 950 degrees C for times up to 3000 h. Following ageing, precipitation of secondary phases was clearly observed with precipitates varying in volume fraction, size, shape and spatial distribution. Several secondary phases were identified via transmission electron microscopy (TEM) and electron diffraction (ED). The orientation relationships between the austenitic matrix and the secondary phases were identified. Interaction and also phase transformation among different types of precipitates, such as between precipitates and the austenitic matrix were observed and an attempt of understanding these phase transformations was carried out. Département SI2M : Microstructures et Contraintes Brechet, Y and Clouet, E and Deschamps, A and Finel, A and Soisson, F Solid State Phenomena SOLID-SOLID PHASE TRANSFORMATIONS IN INORGANIC MATERIALS, PTS 1-2 Mat & Process Sci & Engn Lab; CEA, Tranverse Programme Adv Mat; French Aerospace Lab; Inst Chem, Natl Ctr Sci Res; French Phase Field Network; Lab Etude Microstructures 1012-0394 10.4028/www.scientific.net/SSP.172-174.493 T.Koutsoukis A.Redjaïmia G.Fourlaris