Thermal creep properties of Ti-stabilized DIN 1.4970 (15-15Ti) austenitic stainless steel pressurized cladding tubes

Date: 10/06/2017
Author: Cautaerts, N.; Delville, R.; Verwerft, M.; Dietz, W.

Published in: Journal of Nuclear Materials, Vol. 493, No. 154-167, 10.06.2017, p. 154-167

© 2017 Elsevier B.V.

This paper presents a large database of thermal creep data from pressurised unirradiated DIN 1.4970 Ti-stabilised austenitic stainless steel (i.e. EN 1515CrNiMoTiB or “15-15Ti”) cladding tubes from more than 1000 bi-axial creep tests conducted during the fast reactor R&D program of the DeBeNe (Deutschland-Belgium-Netherlands) consortium between the 1960's to the late 1980's. The data comprises creep rate and time-to-rupture between 600 and 750 °C and a large range of stresses. The data spans tests on material from around 70 different heats and 30 different melts. Around one fourth of the data was obtained from cold worked material, the rest was obtained on cold worked + aged (800 °C, 2 h) material. The data are graphically presented in log-log graphs. The creep rate data is fit with a sinh correlation, the time to rupture data is fit with a modified exponential function through the Larson-Miller parameter. Local equivalent parameters to Norton's law are calculated and compared to literature values for these types of steels and related to possible creep mechanisms. Some time to rupture data above 950 °C is compared to literature dynamic recrystallisation data. Time to rupture data between 600 and 750 °C is also compared to literature data from 316 steel. Time to rupture was correlated directly to creep rate with the Monkman-Grant relationship at different temperatures.