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Aluminium nuclear properties

Although aluminium and its alloys have attractive nuclear properties, they have limited strength, poor compatibility with uranium at high temperatures and low corrosion resistance in water or steam at temperatures above 523 K. Hence their use is restricted to core components in research reactors, where temperatures do not exceed 423 K. However, various parameters, such as water quality, structural design (crevices, galvanic contact with other materials), alloy composition and irradiation, have significant influence on the corrosion resistance of aluminium in research reactors. [Pg.153]

Nuclear Properties. Thanks to its small absorption cross section for thermal neutrons, aluminium is often used in reactor components requiring low neutron absorption. [Pg.194]

No fewer than 14 pure metals have densities se4.5 Mg (see Table 10.1). Of these, titanium, aluminium and magnesium are in common use as structural materials. Beryllium is difficult to work and is toxic, but it is used in moderate quantities for heat shields and structural members in rockets. Lithium is used as an alloying element in aluminium to lower its density and save weight on airframes. Yttrium has an excellent set of properties and, although scarce, may eventually find applications in the nuclear-powered aircraft project. But the majority are unsuitable for structural use because they are chemically reactive or have low melting points." ... [Pg.100]

Specific fillers may be added to add or enhance specific properties in magnetic materials. Alumina, antimony trioxide or magnesium carbonate may be added to improve the flame retardant properties of the composite. The addition of lead oxide or carbide lead is suggested for improve resistance to nuclear radiation. To improve thermal conductivity, alumina, aluminium powder or silicates can be added. Silica, talc, mica or kaolin are indicated to increase the electrical resistance. The inclusion of metal powders, metal oxides or silicates are suggested to thermal absorption improvement. To increase the tensile strength in NR-based materials, carbon black in general, fibres or polymeric materials may be added. [Pg.464]

The main advantage of solid-state NMR spectroscopy in studies of cement-based materials is its ability to detect and quantify amorphous and crystalline phases in an equal manner. This property and the fact that the detected NMR parameters are most sensitive to the local structure, roughly the nearest one to three coordination spheres, makes it a valuable and important supplement to XRD techniques that probe long-range order and crystalline phases. Moreover, the nuclear-spin selectivity often implies that unambiguous structural or quantitative information can be achieved for a subsystem of a complex multicomponent material. For example, Al MAS NMR provides direct information about the aluminium coordination state and, for Portland cement systems, it allows identification of aluminium in tricalcium aluminate, as guest ions in the alite and belite phases, in the AFm and AFt hydration products and as a part of the C-S-H structure, despite a low bulk AI2O3 content of 2-5 wt.% for such systems. [Pg.277]


See other pages where Aluminium nuclear properties is mentioned: [Pg.235]    [Pg.1058]    [Pg.274]    [Pg.1218]    [Pg.281]    [Pg.2]    [Pg.1217]    [Pg.1087]    [Pg.132]    [Pg.148]    [Pg.611]    [Pg.86]    [Pg.94]   
See also in sourсe #XX -- [ Pg.194 ]

See also in sourсe #XX -- [ Pg.194 ]




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Aluminium properties

Nuclear properties

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