SYMPOSIA PAPER Published: 01 January 1990
STP49489S

Irradiation Creep and Swelling of OX16H15M3B Steel and Its Modification 0X16H15M3BP Steel

The results presented concern investigations of the swelling and irradiation creep of OX16H15M3½ steel (0.04 to 0.08% carbon (C), 15 to 17% chromium (Cr), 14 to 16% nickel (Ni), 2.7 to 3.3% molybdenum (Mo), 0.4 to 0.9% niobium (Nb) and its modification OX16H15M3½P (boron content 0.008 to 0.009% by mass) in the solution-annealed (SA), thermal-mechanical processing (TMP) (15% cold-worked + annealing at 800°C for 3 h), and 18% cold-worked conditions.

Pressurized fuel pins having the diameter of the cladding (6.9 × 0.4 mm) and an undersized (180-mm) fuel column were used as specimens for investigations. The fuel pins were irradiated in the BOR-60 reactor in three 19-pin subassemblies up to a maximum burn-up of 10%. The maximum total fluence achieved was 7.8 × 10 26 n / m 2 and 6.7 × 10 26 n / m 2 ( E > 0.1 Me V ), corresponding to a maximum dose of 37 dpa NPT.

Irradiation temperature in the zone of the fuel pins without fuel ranged from 450 to 460°C. Calculated values of stresses in the given test conditions were 10, 90, 120, and 150 MPa.

Steels in the annealed condition showed a void density increase with increasing stresses and a simultaneous decrease of their average volume. With the increase of stress up to 120 MPa, a swelling increase is observed and then, at a stress of 150 MPa, the swelling decrease begins. The swelling level in OX16H15M3½ steel is higher than that in OX16H15M3½P steel at equal stresses (the maximum at 120 MPa is 1.1% and 0.9%, respectively).

The creep deformation of steels in the annealed condition changes linearly owing to applied stresses within the range of 90 to 150 MPa and the creep moduli deduced were 3.2 × 10 6 ( M Pa dpa ) 1 for OX16H15M3½ steel and 1.4 × 10 6 ( M Pa dpa ) 1 for OX16H15M3½P steel.

For steels in the TMP-condition, the changes in swelling were similar to that in annealed steels.

In this case, however, there is no common linear dependence of creep deformation on the level of applied stresses, since the deformation increase occurs up to 120 MPa and its pronounced decrease occurs at 150 MPa.

In the cold-worked OX16H15M3Б steel, no correlation was observed between stresses in the cladding and swelling value. The obtained swelling value ranges from 0.6 to 0.8% for all the investigated stresses.

Author Information

Shamardin, Valentin, K.
V. I. Lenin Research Institute of Atomic Reactors, Dimitrovgrad, Ulyanovsk region, U.S.S.R.
Golovanov, Victor, N.
V. I. Lenin Research Institute of Atomic Reactors, Dimitrovgrad, Ulyanovsk region, U.S.S.R.
Povstyanko, Alexander, V.
V. I. Lenin Research Institute of Atomic Reactors, Dimitrovgrad, Ulyanovsk region, U.S.S.R.
Neustroev, Victor, S.
V. I. Lenin Research Institute of Atomic Reactors, Dimitrovgrad, Ulyanovsk region, U.S.S.R.
Bibilashvili, Yury, K.
All-Union Research Institute of Nonorganic Materials, Moscow, U.S.S.R.
Golovnin, Igor, S.
All-Union Research Institute of Nonorganic Materials, Moscow, U.S.S.R.
Kalashnik, Galina, V.
All-Union Research Institute of Nonorganic Materials, Moscow, U.S.S.R.
Romaneev, Valery, V.
All-Union Research Institute of Nonorganic Materials, Moscow, U.S.S.R.
Price: $25.00
Contact Sales
Related
Reprints and Permissions
Reprints and copyright permissions can be requested through the
Copyright Clearance Center
Details
Developed by Committee: E10
Pages: 753–765
DOI: 10.1520/STP49489S
ISBN-EB: 978-0-8031-8887-7
ISBN-13: 978-0-8031-1266-7