Microstructural study by XRD profile analysis and TEM observations on hydrided recrystallized Zircaloy-4

Journal Article · Sat Feb 01 00:00:00 EST 1992 · Scripta Metallurgica; (United States)

OSTI ID:5703696

Bai, J B ^[1]; Gilbon, D ^[2]; Lebrun, J L ^[3]

---

1. Lab. MSS/MAT, CNRS URA 850, Ecole Centrale Paris, 92295 Chatenay Malabry Cedex (FR)
2. LM3, CNRS URA 1219, ENSAM, 151 Bd. de l'Hopital, 75013 Paris (FR)
3. CEA/DTA/CEREM/DTM/SRMA, C.E. Saclay, 91191 Gif-sur-Yvette Cedex (FR)

Zircaloy-4, used as cladding tube material in the nuclear reactors, may become brittle due to the precipitation of hydrides. During hydride formation, the anisotropic misfit strains between hydrides and the hexagonal-close-packed zirconium matrix results in a preferred orientation of the hydride platelets in the anisotropic stress field caused by non-relieved fabrication residual stresses and misfit stresses. To understand the mechanism of rupture and to predict the threshold stresses for hydride stress orientation, it is necessary to study the residual stresses, especially the microstrain caused by crystalline lattice misfit, in a hydrided specimen. The X-ray diffraction profile analysis is very sensitive to all the microstructure evolution in metallic materials. It is a non-destructive and voluminal technique compared with transmission electron microscope observation. The XRD peak broadening can be related closely with the microstrain in case of hydrided Zircaloy-4, because the hydride formation creates in general a great number of dislocations which contributes especially to the diminution of coherent domain size and to the increase of microstrain. To calibrate the internal microstrain due to precipitation effect of hydrided specimens, XRD profile analysis has also been realized on the non-hydrided specimens deformed by uniaxial tension. In this paper the authors restrict to analyzing the results about the recrystallized state, because more informations about the anisotropic elasticity, plasticity, thermal expansion, neutron diffraction measurement and the crystallographic texture results are available.

• OSTI ID: 5703696
• Journal Information: Scripta Metallurgica; (United States), Vol. 26:3; ISSN 0036-9748
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
22 GENERAL STUDIES OF NUCLEAR REACTORS
CLADDING
MATERIALS TESTING
REACTOR COMPONENTS
STRAIN AGING
ZIRCALOY 4
HYDROGEN EMBRITTLEMENT
MICROSTRUCTURE
NEUTRON DIFFRACTION
X-RAY DIFFRACTION
ANISOTROPY
ELASTICITY
GRAIN ORIENTATION
HEXAGONAL LATTICES
HYDRIDES
PRESSURE TUBES
THERMAL EXPANSION
TRANSMISSION ELECTRON MICROSCOPY
AGING
ALLOY-ZR98SN-4
ALLOYS
CHROMIUM ADDITIONS
CHROMIUM ALLOYS
COHERENT SCATTERING
CORROSION RESISTANT ALLOYS
CRYSTAL LATTICES
CRYSTAL STRUCTURE
DEPOSITION
DIFFRACTION
ELECTRON MICROSCOPY
EMBRITTLEMENT
EXPANSION
HEAT RESISTANT MATERIALS
HEAT RESISTING ALLOYS
HYDROGEN COMPOUNDS
IRON ADDITIONS
IRON ALLOYS
MATERIALS
MECHANICAL PROPERTIES
MICROSCOPY
ORIENTATION
SCATTERING
SURFACE COATING
TENSILE PROPERTIES
TESTING
TIN ALLOYS
TUBES
ZIRCALOY
ZIRCONIUM ALLOYS
ZIRCONIUM BASE ALLOYS
360102* - Metals & Alloys- Structure & Phase Studies
360103 - Metals & Alloys- Mechanical Properties
360106 - Metals & Alloys- Radiation Effects
220200 - Nuclear Reactor Technology- Components & Accessories