Zirconium silicide

The heats of formation have been measured for a range of non-stoicheiometric zirconium carbides ZrC, (x = 0.716—0.990). Differences in details of the bands in the X-ray emission spectra of the zirconium silicides Zr3Si, Zr5Si3, Zr3Si2, and ZrSi2 have been related to the type of crystal lattice of the solid silicide. ... 

Zirconium silicide ZrSi, 12039-90-6 147.396 gray powder 1620 4.88 i HjO, aqua regia s HE... 

The reduction of zirconium tetrachloride in a carrier salt with sodium as a reducing agent may be examined next. Again, as described before, complete deoxidation of the bath before reduction is the essential condition for success, if ductile metal is wanted. Zirconium tetrachloride is soluble in sodium chloride or potassium chloride (48) and a salt with about 25% zirconium tetrachloride can be melted without excessive zirconium chloride losses. Such a bath can even be obtained from powdery commercial zirconium silicide and iron dichloride, which react when heated and deliver a stream of zirconium tetrachloride, contaminated with some titanium tetrachloride and silicon tetrachloride. The gas so produced can be condensed in a fused salt bath such as potassium chloride-sodium chloride, in which only the zirconium tetrachloride dissolves (47), To obtain a low oxide metal after reduction with sodium, the conditions for fluo salt deoxidation must be observed. This process of zirconium production has no special interest, except for obtaining powder for getter purposes. A carrier salt, which might introduce oxide, is not wanted, as the reaction itself liberates sodium chloride. 

When zirconium silicate (ZrSi04) or a mixture of Z1O3 and SiOj is reacted with aluminum in the presence of aluminum oxide and then rdieated, zirconium silicide (ZrSi ) becomes the major product. Titanium dioxide (TiOs) and boron (111) oxide (BgO,) with aluminum similarly form titanium boride (TiBs). If the reduction of the oxides such as TiOg or Si02 with aluminum is performed in the presence of carbon black, the carbides TiC and SiC are formed embedded in aluminum oxide. This subject is also treated in a British patent titled Autothermic Fired Ceramics. ... 

Zirconium silicide synthesis Zirconium diboride Zirconium carbide synthesis... 

MsSis type silicides have several crystal structures. MsSis type binary titanium and zirconium silicides, SisTis and SisZrs, have the hexagonal stmcture with space group of P6s/mcm with the MnsSis-type structure (D8g structure, hP16 or 16H-type). These silicides exhibit high melting points and low densities (below 6.0Mg/m ). 

BK Yen. X-ray diffraction study of mechanochemical synthesis and formation mechanisms of zirconium carbide and zirconium silicides. J AUoys Compos 268 266, 1998. 

The silicides of major industrial importance are the disilicides of the refractory metals molybdenum, tantalum, titanium, tungsten, vanadium, and zirconium.pl] These compounds are of great interest par-... 

The fuels are finely powdered metals (2.0-10.0 g) among which titanium, zirconium, manganese, tungsten, molybdenum and antimony are very common. Sometimes, non-metal powders such as boron and silicon (for fast burning delays), binary alloy powders such as ferrosilicon, zirconium-nickel, aluminum-palladium and metal compounds such as antimony sulfide, calcium silicide etc. are also used. 

Fuels used include antimony sulfide (which also acts as a frictionator), gum arabic (which also acts as a binding agent), calcium silicide (which also acts as a frictionator), nitrocellulose, carbon black, lead thiocyanate, and powdered metals such as aluminum, magnesium, zirconium, or their alloys. 

Antimony sulfide Tetracene Calcium silicide Lead dioxide Aluminum powder Ground glass Lead hypophosphite Lead peroxide Zirconium Nitrocellulose Pentaerythritol tetranitrate Gum type binder... 

There are several examples of M-Si systems. Silicides of composition M2 Si, MSi, and MSi2 are known for both metals. Zirconium also forms the Zrs Si2 phase and hafhiiun the Hfs Sis phase (see Silicon Inorganic Chemistry). All the silicides are insoluble in all mineral acids (except HF), and, unlike TiSi2, in 10% aqueous KOH. 

J. C. Barbour The Diffusion of Nickel in Amorphous Nickel-Zirconium Alloys and the Composition Analysis of Nickel-Silicide Formation in Lateral Diffusion Couples. Ph.D. Thesis, Dept, of Mater. Sci. Cornell Univ., (1986)... 

As to the chemical composition of phases, one sample of it is shown in Table 1. In spite of all the problematicity of chemical microanalysis of such a kind it is seen that except silicides silicon and zirconium prefer [3-phase. 

With silicon there are formed the silicide ZrSi2, the natural silicate ZrSiO, and various complex silicates. Native zircon as well as certain other zirconium ores are quite strongly radioactive, and when heated they display luminescence and suffer a change in density and color. Zircon also shows2 the property of triboluminescence. 

Titanium, Zirconium and Thorium Silicides TiSi 3, ZrSi g,... 

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