Titanium Metal Powder

Titanium carbide may be prepared by a thermochemical reaction between finely divided carbon and titanium metal powder. The reaction proceeds exothermically. 

Pyrophoricity and detonation behaviour of titanium hydride powders of various particle sizes were studied in comparison with those of titanium metal powders [1]. Maximum dust explosion pressures of 8.2 bar, with a maximum rate of rise of 816 bar/s have been recorded [2]. 

The spectrum of titanium metal foil is in Fig. 23. The foil, originally of 12/t thickness, was reduced by etching in HF to about 4/. A corresponding spectrum of titanium metal powder (not shown here) contained the same peaks but with only about half the amplitude, and with greater scatter of data points. This is an illustration of the advantages of having uniformity of thickness, which is especially difficult to achieve with metal powders. The titanium metal spectrum appears to be Kronig type fine structure. 

In conventional ammunition lead, antimony, and barium are emitted when the ammunition is discharged. These three elements are undesirable from a health viewpoint and pose a major problem for firearms instructors in indoor firing ranges, as they are exposed to an unhealthy environment each working day. To solve this problem Dynamit Nobel AG developed a nontoxic primer composition called Sintox. Lead styphnate is replaced by 2-diazo-4,6-dinitrophenol (diazole) and the barium nitrate and antimony sulfide are replaced by a mixture of zinc peroxide and titanium metal powder. 

The nylon-coated bullets from Smith Wesson and the Geco TMJ bul-let/new primer composition, although effective in markedly reducing the lead levels, did not totally eliminate the problem. In 1983, Dynamit Nobel introduced 9 mmP caliber ammunition with a TMJ bullet and a primer free of lead, antimony, barium. The new primer type was called Sintox. A typical Sintox primer composition contains 15% diazodinitrophenol (DDNP) and 3% tetracene as the explosive ingredients, 50% zinc peroxide as the oxidizer, 5% of 40-pm size titanium metal powder, and 27% nitrocellulose as propellant powder.202 As expected, other munitions manufacturers eventually introduced similar ammunition, some with primers that were lead free but containing antimony and barium and others free of lead, antimony, and barium. The objective was to produce ammunition which performed satisfactorily in every way and did not produce any toxic product on discharge. 

Anatase samples doped with 0T, 1 and 5 atom % sulphate ion impurity were prepared by the method reported earlier.6 Spectrographically standardized titanium metal powder supplied by Johnson and Matthey, London, was used for the purpose. The lattice constants of these anatase samples remained the same within experimental error (a = 3-771 + 005 A and c = 9-498 -013 A). 

Titanium metal powder was reacted with water in a ratio of 1 2 in a gold capsule under hydrothermal conditions of 100 MPa for 3 h at temperatures of up to 700°C. Figure 1.5 shows the results. 

The titanium species prepared in this way is far more reactive than commercial titanium metal powder (100 mesh), which does not react with trichlorofluoromethane even after several days at room temperature. The ratio of cis/trans-isomers of 1-chloro-l-fluorocyclopropanes formed suggests that free carbene is generated. It is possibly formed via the pathway shown below. ... 

German RM (2013) Progress in titanium metal powder injection molding. Materials 6 3641-3662... 

Norgate, T. and Wellwood, G. (2006) The potential applications for titanium metal powder and their life cycle impacts. JOM J. Miner. Metals Mater. Soc., 58(9), 58-63. 

Armstrong A process for making titanium metal powder, developed by Don Armstrong at International Titanium Powder (ITP) in Woodbridge, IL. Acquired by Cristal USA in 2008 and commercialized in Ottawa, IL, since 2011. Essentially a continuous version of the Hunter process, in which titanium tetrachloride is reacted with metallic sodium. 

Metalysis A one-step process for making titanium metal powder from mineral rutile. Developed by Metalysis in Rotherham, Yorkshire, and announced in 2012. 

Polar An electrolytic process for making titanium metal powder from titanium dioxide. Broadly similar to the FFC process. Developed by BHP Billiton and acquired by QinetiQ in 2006. 

---