Zirconium-niobium alloy

Figure 40 P secondary ion image on cross section of uranium-niobium-zirconium alloy. (From Ref. 129.)...

Hafnium-free zirconium alloys containing tin or niobium are used for tubing to hold uranium oxide fuel pellets inside water-cooled nuclear reactors. Zirconium —niobium alloys are used for pressure tubes and stmctural components in Canadian, the former USSR, and Germany reactor designs. 

Niobium-Zirconium-Titanium Niobium alloys containing zirconium and titanium have improved resistance to high-temperature water and have been evaluated for use in pressurised-water nuclear reactors. 

The pyrogallol method has been used for determining tantalum in ores and minerals [130, steels [131], niobium [132], zirconium alloys [133], and beryllium and its oxide [134]. 

The method involving the Mo-V-P acid has been used in determinations of phosphorus in biological tissues [127], plant material [128], fruits [129], fish products [130], foodstuffs [131], phosphate minerals [132], cast iron and steel [133,134], niobium, zirconium and its alloys, titanium and tungsten, aluminium, copper, and white metal [135], nickel alloys [134,135], metallurgy products [136], molybdenum concentrates [137], silicon tetrachloride [7], cement [138], and lubricants[139]. The flow injection technique has been applied for determining phosphate in minerals [140] and in plant materials [141]. 

Zr-2.5 Nb [zirconium alloyed with 2.5 w/o (weight percent) niobium] has better mechanical properties than zircaloy, but is conoded more rapidly by water containing oxygen, such as is found in boiling-water reactors. It was the material prefened in 1971 [El] for pressure tubes in Canadian pressurized-water reactors. 

TEST APPARATUS AND TENSILE PROPERTIES OF NIOBIUM-ZIRCONIUM SUPERCONDUCTOR ALLOY WIRE IN THE TEMPERATURE RANGE 300° TO 4.2°K... 

Superconducting materials can be divided into two general categories—brittle and ductile. The brittle superconductors consist of the intermetallic compounds such as columbium-tin (CbaSn) and vanadium-gallium (VsGa). The ductile superconductors consist of most of the elemental metals as well as alloys such as niobium-zirconium. 

At the present state of the art, most interest centers around the intermetallic compounds and alloys w hich have a combination of high critical temperature and high critical field. From a practical standpoint, the alloys, notably niobium-zirconium, are of more interest to end users and designers because the brittle materials present a greater number of manufacturing and fabrication problems. 

Test Apparatus and Tensile Properties of Niobium-Zirconium Superconductor Alloy Wire 125... 

In order to determine in-reactor creep rates of Indian made Zirconium alloys, it is decided to irradiate the pressurised capsules made of Zircaloy-2 and Zircaloy-4 Niobium alloys in FBTR. Towards this, six pressurised capsules have been fabricated and ready for irradiation. 

The zirconium alloys used in PWR nuclear components consist of both zirconium-tin alloys and zirconium-niobium alloys. PWRs have historically used Zircaloy-4, which consists of 98.23 weight % zirconium with 1.45% tin, 0.21% iron, 0.1% chromium, and 0.01% hafnium. 

F 1713, Specification for Wrought Titanium-13 Niobium-13 Zirconium Alloy for Surgical Implant Applications... 

In the nuclear industry, stainless steel was used to clad the uranium dioxide fuel for the first-generation reactors. But by 1965, the force of neutron economy had made zirconium alloys the predominant cladding material for water-cooled reactors. There was a widespread effort to develop strong, corrosion-resistant zirconium alloys. Noticeably, the Ozhennite alloys were developed in the Soviet Union for use in pressurized water and stream. These alloys contain tin, iron, nickel, and niobium, with a total alloy content of 0.5-1.5%. The Zr-1% Nb alloy also is used in the Soviet Union for pressurized water and steam service. Researchers at Atomic Energy of Canada Ltd. took a lead from the Russians zirconium-niobium alloys and developed the Zr-2.5% Nb alloy. This alloy is strong and heat-treatable. It is used either in a cold-worked condition or a quenched-and-aged condition. 

Zirconium and its alloys can be classified into two major categories nuclear and nonnuclear. They all have low alloy contents. They are based on the a structure with dilute additions of solid solution strengthening and a-stabilizing elements like oxygen and tin. However, in niobium-containing alloys, there is the presence of some niobium-rich P particles. 

It was decided to use 30 cold-worked Zlrcaloy-2 as a pressure tube material for the Winfrith reactor because this was the only zirconium alloy on which fabrication technology was sufficiently advanced and about which extensive knowledge on physical, mechanical and corrosion properties was available, largely from North American sources. An undeveloped alternative was an alloy based on a zirconium composition containing 2.5 by weight niobium. In the solution treated, quenched and aged condition this alloy shows markedly superior mechanical properties to Zircaloy-2, and In the event it was possible to Include a small number of heat treated pressure tubes In the Winfrith reactor. 

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