Hydrogen in zirconium alloys: A review

When zirconium alloys are used in water-cooled reactors, they are subjected to waterside corrosion. The emphasis of this chapter is on uniform oxidation and hydrogen embrittlement. The twin processes of oxidation and hydriding are described comprehensively in terms of their underlying mechanisms.

Corrosion of Zirconium Alloys

Hydrogen-enhanced degradation and oxide effects in zirconium alloys for nuclear applications

Stress-reorientation of hydrides and hydride embrittlement of Zr-2.5 wt% Nb pressure tube alloy

Terminal solid solubility of hydrogen in Zr-alloy pressure tube materials

Microstructural evolution in and flow properties of Zr–2.5Nb pressure tube material at elevated temperature

Effects of δ‐hydride precipitated at a crack tip on crack instability in Zircaloy‐4

In heavy water cooled nuclear reactors, Zr–2.5Nb alloy is used for pressure tubes under cold worked and stress relieved (CWSR) condition in Canadian Deuterium Uranium (CANDU) reactors and under quenched and aged condition in RBMK and Fugen reactors. Because of its ease of use and the lower cost of fabrication, most of the work reported in literature is focused on the development and characterization of cold worked and stress relieved pressure tube material. However, recent work showed that the tubes manufactured using quenched and aged route showed a lower and predictable rate of in-reactor deformation during reactor operation as compared to those fabricated using the CWSR route. One of the important stages in the fabrication of heat treated pressure tube material is solution heat treatment (SHT), which governs the microstructure and hence, the mechanical properties of pressure tubes. Usually, SHT is carried out in two phase (α + β) region at a temperature closer to the β transus. The present work characterizes the influence of different SHT parameters such as soaking temperature (850, 870, and 890°C) and duration (15 and 30 min) on microstructure, texture, and Nb partitioning between phases and mechanical properties such as tensile properties, hardness, and fracture toughness. Fracture toughness parameters were determined as per ASTM standard E1820-11. Optical microscopy was used for microstructure, X-ray diffraction for texture, and EPMA for Nb partitioning investigation. The fracture surfaces were examined using SEM.

Influence of Soaking Temperature and Time on Microstructure and Mechanical Properties of Water Quenched Zr–2.5Nb Alloy

Restructuring of water harvesting ponds and ground water recharge.

ASTM E1820-11, the most widely adopted standard for the determination of fracture toughness parameters, recommends two ductile crack growth correction methods for the evaluation of the J-integral parameter, viz., the basic test (BT) method and the resistance curve test (RC) method. In the present work, a comparison between the fracture toughness parameters obtained using these two methods for heat-treated Zr-2.5Nb alloy at 25°C and 300°C is presented. In order to examine the influence of a material's microstructural condition on the fracture toughness results obtained via these two methods, Zr-2.5Nb alloy was investigated under six solution heat-treated conditions after getting soaked at 850°C, 870°C, or 890°C for either 15 min or 30 min followed by water quenching. The BT method predicted a higher J parameter than the RC method for a given crack length. This deviation in the magnitude of J increased with increasing crack length and was found to be almost twice as much at room temperature as the deviation observed at 300°C. For smaller crack lengths (i.e., up to a/W

R.N. Singh

Papers

Microstructural evolution in and flow properties of Zr–2.5Nb pressure tube material at elevated temperature

Effects of δ‐hydride precipitated at a crack tip on crack instability in Zircaloy‐4

Influence of Soaking Temperature and Time on Microstructure and Mechanical Properties of Water Quenched Zr–2.5Nb Alloy

Restructuring of water harvesting ponds and ground water recharge.

Comparative Study of Basic Test and Resistance Curve Methods for Fracture Toughness Evaluation of Heat-Treated Zr-2.5Nb Alloy