Zirconium and alloys

Tabic 5. ASTM Grades and Commercial Designations of Commercial Zirconium and Alloys... 

The activity must be separated from /J -emitters formed from the matrix (zirconium and alloying elements) and also from 0 and formed via the C(d,n) N, N(d,n) 0 and 0(d,n) F reactions. can be separated as C02 formed during dissolution of the sample in an oxidizing acid mixture or during combustion in an oxygen stream. 

Small amounts of yttrium (0.1 to 0.2%) can be used to reduce the grain size in chromium, molybdenum, zirconium, and titanium, and to increase strength of aluminum and magnesium alloys. 

R. K. McGeary, inM Symposium on Zirconium and Zirconium Alloys, American Society for Testing and Materials, Philadelphia, 1953, p. 168. 

Chlorination. In some instances, the extraction of a pure metal is more easily achieved from the chloride than from the oxide. Oxide ores and concentrates react at high temperature with chlorine gas to produce volatile chlorides of the metal. This reaction can be used for common nonferrous metals, but it is particularly useful for refractory metals like titanium (see Titanium and titanium alloys) and 2irconium (see Zirconium and zirconium compounds), and for reactive metals like aluminum. 

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. 

O. Kubaschewski, ed.. Zirconium Physico-Chemical Properties of its Compound and Alloys, International Atomic Energy Agency, Vieima, 1976, p. 8. 

Boron forms B—N compounds that are isoelectronic with graphite (see Boron compounds, refractoryboron compounds). The small size also has a significant role in the interstitial alloy-type metal borides boron forms. Boron forms borides with metals that are less electronegative than itself including titanium, zirconium, and hafnium. 

Many elemental additions to copper for strengthening and other properties also deoxidize the alloy. A side benefit of such additions is elimination of susceptibihty to hydrogen embrittlement. Such deoxidizing additions include beryllium, aluminum, siUcon, chromium, zirconium, and magnesium. 

Zirconium and zirconium alloys. The possibihty of deterioration of zirconium and zirconium alloys above 315°C (600°F). 

Phase Transformations in Titanium- and Zirconium-Based Alloys... 

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 growth of nuclear engineering with its specialised demands for materials having a low neutron absorption coupled with adequate strength and corrosion resistance at elevated temperatures, has necessitated the production of zirconium in relatively large commercial quantities. This specific demand has resulted in development of specially purified zirconium, and certain zirconium alloys, for use in particular types of nuclear reactor. 

It should be noted that swarf from a zirconium-titanium alloy containing approximately 50% by weight of each element is prone to pyrophoricity in air. It has also been reported that when zirconium is welded to titanium, the welded zone is much more sensitive to corrosion than either of the parent metals. If, therefore, it is proposed to use my construction in which zirconium is welded to titanium, caution should be observed in the machining of welds, and the corrosion behaviour of the weld should be checked by prior testing in the environment with which the construction will be employed. 

Test method for sandwich corrosion test Recommended practice for preparing, cleaning, and evaluating corrosion test specimens Practice for aqueous corrosion testing of samples of zirconium and zirconium alloys Test method for corrosion testing of products of zirconium, hafnium and their alloys in water at 633 K or in steam at 673 K [metric] Recommended practice for conventions applicable to electrochemical measurements in corrosion testing... 

Phillips, J. F. Dissolution of Oxide-Coated Zirconium and Zirconium Alloys, U.S. AEC Report BNWL-600, Pacific Northwest Laboratory, Richland, WA, 1968. 

The zone elution method has been used for quantitative estimation or recovery of heavy metals in plants and vegetable juices [29], mercury (11) in river and waste waters [52], zinc in different environmental samples [46], nickel and copper in alloys [53], zirconium in Mg-Al alloys [22], cobalt, zinc, nickel, and copper in natural water and alloy samples [54], thiocyanate in spiked photogenic waste water [55], and aluminum in bauxite ores [42],... 

Zirconium and zirconium alloys are used in the nuclear industry, because of their low neutron absorption cross-section and resistance to hot water at high pressures. 

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