A study on texture stability and the biaxial creep behavior of as-hydrided CWSR Zircaloy-4 cladding at the effective stresses from 55 MPa to 65 MPa and temperatures from 300°C to 400°C

Journal Article · Wed Jun 01 04:00:00 EDT 2022 · Journal of Nuclear Materials

DOI:https://doi.org/10.1016/j.jnucmat.2022.153688· OSTI ID:2574363

Lan, Kuan-Che; Chuang, Chih-Pin; Tung, Hsiao-Ming; Mo, Kun; Miao, Yinbin; Liu, Xiang; Lee, Hoon; Park, Jun-Sang; Almer, Jonathan; Stubbins, James F.

The creep rupture of high burnup used nuclear fuel (> 45 GWD/MTU) cladding is regarded as one of the failure mechanisms during long-term dry storage. A high amount of zirconium hydride in the cladding matrix would degrade the mechanical properties of the cladding especially leading to delayed hydride cracking. To better understand the influence of zirconium hydride on the biaxial thermal creep performance and the crystalline texture stability of Zircaloy-4 cladding, the pressurized tube technique is applied to test the durability of the as-hydrided material. Tests were performed on as-received Zircaloy-4 tubular specimens as well as-hydrided ones with targeted 300 wt parts per million (wppm) or 750 wppm hydrogen. The biaxial creep experiments were conducted at temperatures from 300 degrees C to 400 degrees C and at equivalent stresses at mid-wall from 55 MPa to 65 MPa. The hydridation process prior to creep tests induces the formation of FCC delta-hydride platelets along the circumferential direction of the tube. This alignment and phase structure of hydride show no significant change after biaxial creep tests. The creep strain-rate negatively depends on the hydrogen content. The synchrotron wide-angle X-ray diffraction (WAXD) technique and electron backscatter diffraction (EBSD) analysis were applied for the study of the crystallographic orientation relationship. zirconium-to-hydride grain orientation follows Shoji-Nishiyama crystallographic relationship. This relationship is stable before and after creep deformation. These results of creep performance and texture stability of Zircaloy-4 claddings can help support the design basis of interim and long-term dry storage facilities.

• Research Organization: Argonne National Laboratory (ANL)
• Sponsoring Organization: US Department of Energy; Ministry of Education, Culture, Sports, Science and Technology (MEXT) of Japan; USDOE Office of Science; USDOE Office of Nuclear Energy - Nuclear Energy University Programs (NEUP); Ministry of Science and Technology of Taiwan (MOST)
• DOE Contract Number: AC02-06CH11357
• OSTI ID: 2574363
• Journal Information: Journal of Nuclear Materials, Journal Name: Journal of Nuclear Materials Vol. 564; ISSN 0022-3115
• Country of Publication: United States
• Language: English

Related Subjects

creep
tensile
Zircaloy
hydride
hydride
texture
texture dry-storage