Physical Properties of Tungsten

W+40.68 A, W+60.65 A. Metallic radius 1.37045 A. Other important physical properties of tungsten are given under Chemical Elements. 

Some of the physical properties of tungsten are given in Table 3 further property data ate available (12-14). For thermodynamic values, References 5,15, and 16 should he consulted. Two values ate given for the melting point. The value of 3660 K was selected as a secondary reference for the 1968 international practical temperature scale. However, since 1961, the four values that have heen reported ranged from 3680 to 3695 and averaged 3688 K. 

The chemical and physical properties of tungsten(V) chloride are well-established.8-11 It melts at 248°, boils at 275.6°, and crystallizes in very dark blue-green needles which decompose quickly when exposed to moist air. The very faint blue-green vapor of tungsten(V) chloride is in contrast to the yellowish-red vapor of tungsten (VI) chloride. It is only very slightly soluble in nonpolar organic solvents and reacts with most of the polar solvents. 

The physical properties of tungsten hexafluoride are given in Table 5 [54-57], Tungsten hexafluoride is a colorless gas at room temperature and is ten times as heavy as air. It condenses into a pale yellow liquid at 17.5 C and forms a white solid below 2.3°C [54]. The vapor pressure is given by the following equations [56] ... 

H. A. Pastor, Microstructure-Independent Physical Properties of Tungsten, in The Metallurgy of Doped/Non-Sag Tungsten, (E. Pink and L. Bartha, Eds.), Elsevier, London (1989). 

TABLE 5.12. Important Physical Properties of Tungsten Powder... 

Selected physical properties of rhenium are summarized ia Table 1. The metal is silvery-white and has a metallic luster. It has a high density (21.02 g/cm ). Only platinum, iridium, and osmium have higher densities. The melting poiat of rhenium is higher than that of all other elements except tungsten (mp 3410°C) and carbon (mp 3550°C). 

For a comparison of the physical properties of tantalum, tungsten, molybdenum, platinum, oopper and nickel, see Balke, Chem. Met. Mng., 1922, 27, 1273. 

The thin yellow flakes of tungsten(VI) dichloride dioxide, and the compounds to be mentioned later as well, are sensitive to atmospheric moisture. Therefore the reaction tubes must be opened in a dry nitrogen atmosphere and stored either under vacuum or in a dry inert gas. The detailed physical and chemical properties of tungsten(VI) dichloride dioxide are described in the literature.1... 

In addition, some physical and chemical properties of tungsten will... 

The aim of alloying tungsten is to improve its chemical, physical, and mechanical properties at both ambient conditions and elevated temperatures. Beyond that, it is possible to combine the useful properties of tungsten with those of the alloying additives. 

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