In situ characterizations of phase transformations kinetics in the Ti17 titanium alloy by electrical resistivity and high temperature synchrotron X-ray diffractionMATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING, 476(1-2):60-68
Resume: The beta(BCC) -> alpha(HCP) + beta(BCC) phase transformation kinetics of the beta-metastable titanium alloy Ti17 was studied by in situ high energy X-ray diffraction (XRD) and electrical resistivity. The use of synchrotron radiation (E = 89.12 keV, lambda = 0.01402 nm) allowed to characterize specimens 6 mm in diameter, limiting thus oxidation effects. The alpha + beta -> beta phase transformation kinetics was characterized during continuous heating up to the P temperature range. The beta -> alpha + beta transformation was studied in isothermal conditions (dwell at 708 degrees C or 750 degrees C) and during continuous cooling (cooling rates of 0.05 degrees C/s, 0.1 degrees C/s and 0.61 degrees C/s). The evolutions of the phase fractions are analyzed and compared to kinetics measured by electrical resistivity, showing a good correlation between both methods. In addition, the evolutions of the cell parameters of each phase obtained from XRD patterns are analyzed in regard of the transformation kinetics. (C) 2007 Elsevier B.V. All rights reserved.
Equipe: Département SI2M : Microstructures et Contraintes