Injection metallurgy

Originally injection metallurgy was used to remove sulfur. Nowadays, however, this technique is also used for deoxidation and slag modification. Argon is used as a carrier gas to transport the powder into the melt and the powder, e.g. aluminum or fer-rosilicon, is so fine that it is fluidized in the gas stream, see Figure 8.27. 

Figure 8.27 Injection metallurgy for deoxidation and slag modification. (Reprinted from the booklet Steel with permission from Employers Association of the Swedish Steel and Metal Industry, Stockholm.)...

In model experiments using molten steel, Cu is often chosen as a tracer, but the sampling is made discretely to determine mixing time. It is desirable to develop a simplified method capable of measuring the concentration of tracer in a molten metal bath continuously. Such a method would also be useful for judging whether or not fine powder disperses uniformly in the molten metal bath according to the established powder injection metallurgy. 

Mori K, Sano M (1981) Process kinetics in injection metallurgy. Testsu-to-Hagane 67 672-695... 

Castillejos EAH, Brimacombe JK (1986) SCANINJECT IV, Part 1, No. 16, 4th Conf. on Injection Metallurgy, MEFOS, Lulea, Sweden, paper no. 16.1... 

Above its melting point of 327° C, polytetrafluoroethylene has some properties more like a rubber than a liquid. The instantaneous Young s modulus is 2—3 X 107 dynes/cm2, and the melt viscosity is about 10u poises at 380° C (Nishioka and Watanabe). Because of this very high melt viscosity, it is not feasible to process the polymer by conventional extrusion or injection molding. Instead, techniques similar to those of powder metallurgy are employed. These involve three basic steps. 

J. Janz, and W. Weiss, Injection of waste plastics into the blast furnace of Stahlwerke Bremen. La Revue de Metallurgie-CIT. 1219-1226, (1996). 

The method involving the Mo-V-P acid has been used in determinations of phosphorus in biological tissues [127], plant material [128], fruits [129], fish products [130], foodstuffs [131], phosphate minerals [132], cast iron and steel [133,134], niobium, zirconium and its alloys, titanium and tungsten, aluminium, copper, and white metal [135], nickel alloys [134,135], metallurgy products [136], molybdenum concentrates [137], silicon tetrachloride [7], cement [138], and lubricants[139]. The flow injection technique has been applied for determining phosphate in minerals [140] and in plant materials [141]. 

K. R. Robilliard, International Symposium on Injection in Process Metallurgy, The Minerals, Metals and Materials Society, 1991, pp. 181-198. 

Another serious problem that arises in all C02 floods, and must be considered here, is corrosion. As is well known, solutions of C02 in water dissociate to form carbonic acid. This is a weak acid and does not cause much trouble in fresh water floods. However, in brine instead of pure water, C02 does become much more corrosive, and the particular composition of the brine has a great effect. These difficulties can be made worse by the presence of surfactant that can remove coatings emplaced by corrosion inhibitors. This difficulty could occur in both the injection as well as in the production facilities. In many fields, special metallurgy has been needed in critical elements of the hardware. Not much in the way of general principles can be given, except that, in designing a C02 flood, the modification of existing problems is to be expected. 

H. Ma, Applications of Flow Injection Analysis in Metallurgy and Geology. A Review [in Chinese]. Lihua Jianyan, 22 (1985) 374. 

Ebe93] Ebenhdch, J ter Maat J (1993) Ceramic Injection Molding with a Polyacrylat Based Binder System. In Advances of Powder Metallurgy and Particulate Materials, vol 5, Powder Injection Molding. Metall Powder Industires Federation, Princeton, pp 73-89... 

Pis are essentially nonfiisible and difficult to fabricate by conventional shaping processes. Parts are fabricated by techniques ranging from powder metallurgy methods to modifications of conventional injection, transfer, compression, and extrusion that include ram instead of screw plastication (Chapter 5). 

A.R. Musson, M.W. Gammon, I.M. Hitchens and S.P. Mathew, The Development of Tuyere Injection Technology for the ISF at Britannia Zinc Ltd , Zinc and Lead Processing. J.E. Dutrizac, J.A. Gonzalez, G.L. Bolton and P. Hancock, Eds., Canadian Institute of Mining, Metallurgy and Petroleum, Montreal, Canada, 1998,265-276. 

A. Kawasaki, R. Watanabe, Y. Kuroki Preparation of monosized spherical powders of Pb-Sn alloy by pulsated orifice injection method, Proceedings of the Powder Metallurgy World Congress, Paris, vol. 1, pp. 365-368 (1994). 

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