Isothermal stress reorientation of hydrides in Zr-2.5Nb pressure tube alloy

Autor: Apu Sarkar, G. Avinash, R.V.S. Krishna Vidhan, Saurav Sunil, R.N. Singh, T.N. Murty
Rok vydání: 2022
Předmět:
Zdroj: Journal of Nuclear Materials. 559:153440
ISSN: 0022-3115
DOI: 10.1016/j.jnucmat.2021.153440
Popis: The precipitation of hydrides normal to the transverse direction in Zr-2.5%Nb pressure tube alloy when cooled under stress above a threshold value, is known as stress reorientation of hydrides. The ex-situ threshold stress values reported in the literature were determined using pre-charged samples heated to a peak temperature to dissolve all the hydrides, cooled to reorientation temperature followed by cooling under stress from reorientation temperature. Leger and Donner performed in-situ reorientation experiments using samples having hydride deposited on its surface. In both cases, hydride reorientation occurred during cooling. In the present investigation, for the first time, experiments were done to study the reorientation phenomenon using in-situ gaseous charging of samples under stress at a constant temperature using a specially designed set up. It is expected that the threshold stress determined by in-situ method used in the present investigation will more closely resemble the formation of radial hydrides under reactor operating conditions. In this work, the threshold stress values for reorientation of hydrides in Zr-2.5%Nb pressure tube material were determined using both in-situ and ex-situ methods.
Databáze: OpenAIRE