Cooldown-induced hydride reorientation of hydrogen-charged zirconium alloy cladding tubes

AbstractCladding failure of fuel rods caused by hydride-induced embrittlement is a reliability concern for spent nuclear fuel after extended burnup. Uncertainties in the cladding temperature, cladding stress, oxide layer thickness, and the critical stress value for hydride reorientation preclude an assessment of the cladding failure risk. A set of micromechanical models for treating oxide cracking, blister cracking, delayed hydride cracking, and cladding fracture was developed and incorporated in a computer model. Results obtained from the model calculations indicate that at temperatures below a critical temperature of 318.5 °C [605.3 °F], the time to failure by delayed hydride cracking in Zr-2.5%Nb decreased with increasing cladding temperature. The overall goal of this project is to develop a probabilistic-micromechanical methodology for assessing the probability of hydride-induced failure in Zircaloy cladding and thereby establish performance criteria.

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Control of hydrogen absorption by nickel films obtained upon magnetic spraying of zirconium alloy using the thermoEMF method

Industrial laboratory Diagnostics of materials ◽

10.26896/1028-6861-2020-86-8-32-37 ◽

2020 ◽

Vol 86 (8) ◽

pp. 32-37

Author(s):

V. V. Larionov ◽

Xu Shupeng ◽

V. N. Kudiyarov

Keyword(s):

Magnetron Sputtering ◽

Hydrogen Concentration ◽

Hydrogen Absorption ◽

Zirconium Alloy ◽

Hydrogen Adsorption ◽

Zirconium Alloys ◽

Nickel Film ◽

Protective Film ◽

Nickel Films ◽

Hydrogen Penetration

Nickel films formed on the surface of zirconium alloys are often used to protect materials against hydrogen penetration. Hydrogen adsorption on nickel is faster since the latter actively interacts with hydrogen, oxidizes and forms a protective film. The goal of the study is to develop a method providing control of hydrogen absorption by nickel films during vacuum-magnetron sputtering and hydrogenation via measuring thermoEMF. Zirconium alloy E110 was saturated from the gas phase with hydrogen at a temperature of 350°C and a pressure of 2 atm. A specialized Rainbow Spectrum unit was used for coating. It is shown that a nickel film present on the surface significantly affects the hydrogen penetration into the alloy. A coating with a thickness of more than 2 μm deposited by magnetron sputtering on the surface of a zirconium alloy with 1% Nb, almost completely protects the alloy against hydrogen penetration. The magnitude of thermoemf depends on the hydrogen concentration in the zirconium alloy and film thickness. An analysis of the hysteresis width of the thermoEMF temperature loop and a method for determining the effective activation energy of the conductivity of a hydrogenated material coated with a nickel film are presented. The results of the study can be used in assessing the hydrogen concentration and, hence, corrosion protection of the material.

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To the issue of corrosion of occluders from beta-zirconium alloy in experimental study of endovascular devices for the closure of arterial duct

UMJ Heart & Vessels ◽

10.30978/hv2018238 ◽

2018 ◽

Vol 0 (2) ◽

pp. 38-45

Author(s):

Yu. V. Panichkin ◽

V. P. Zakharova ◽

Yu. L. Konopliova ◽

A. Yu. Gavrilishin ◽

E. V. Beshlyaga ◽

...

Keyword(s):

Experimental Study ◽

Zirconium Alloy ◽

Arterial Duct ◽

Endovascular Devices

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The vanadium-zirconium alloy system

10.31274/rtd-180813-14668 ◽

1954 ◽

Author(s):

John Trew Williams

Keyword(s):

Zirconium Alloy ◽

Alloy System

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SCHMELZMETALL HOVADUR CCZ

Alloy Digest ◽

10.31399/asm.ad.cu0912 ◽

2020 ◽

Vol 69 (9) ◽

Keyword(s):

Thermal Conductivity ◽

Spot Welding ◽

Zirconium Alloy ◽

High Strength ◽

Heat Treating ◽

Softening Temperature ◽

Aged Condition ◽

Heat Treated ◽

High Softening Temperature ◽

Made In

Abstract Schmelzmetall Hovadur CCZ is a heat-treatable, copper-chromium-zirconium alloy. In the solution heat-treated and artificially aged condition, this alloy exhibits high thermal and electrical conductivity along with high strength and a high softening temperature. Hovadur CCZ evolved from CuCr1 (CW105C), a precipitation-hardenable alloy first made in the 1930s for spot welding electrodes, for which strength and hardness at temperatures up to 500 °C (930 °F), as well as good electrical and thermal conductivity, are essential. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on forming, heat treating, machining, and joining. Filing Code: Cu-912. Producer or source: Schmelzmetall AG.

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