Senior Scientific Officer, Metallurgy Division, AERE Harwell, Oxfordshire,
Senior Metallurgist, Rolls-Royce and Associates Ltd., Derby,
Higher Scientific Officer,
Pages: 18 Published: Jan 1984
The irradiation growth behavior of annealed polycrystalline Zircaloy-2 has been investigated in the DIDO reactor at Harwell at fluences up to 1 × 1025 neutrons (n)m−2 (E > 1 MeV) and in the temperature range 513 to 673 K. Growth strain data for two batches of rolled, annealed Zircaloy plate did not obey the G ∝ (1 − 3f) texture relationship with transverse direction specimens (f = 0.25 and f = 0.35) exhibiting negative growth following an initial positive transient. The effect of irradiation temperature on growth was not marked over the range studied except that, at 673 K, growth strains appeared to saturate at low fluences. Apart from this, longitudinal and transverse growth strains decreased slightly with increasing temperature above 573 K. Specimens of large grained, β-annealed Zircaloy with a completely random structure showed virtually no sensitivity of growth to either fluence or temperature under the conditions studied. The apparently anomalous growth behavior of the transverse annealed plate materials cannot be explained by the influence of density changes during growth. It is proposed that the deviation from the expected growth-texture relationship is due to the effects of intergranular stresses which occur as a result of, and in opposition to, irradiation growth in polycrystalline materials.
Zircaloy, zirconium alloys, annealed, recrystallized, irradiation growth, neutron irradiation, texture, temperature, fluence
Paper ID: STP34481S