Costed powder

A principal motive for developing consoHdation techniques is to reduce cost by improving yields. For aircraft parts, the so-called buy-to-fly ratio is ca 6 1. Product yields based on sponge are shown in Figure 8. The potential improvements in yield using powder are obvious. However, reHable, low cost powder-production techniques have not yet been fully developed as of this writing. 

Water Atomization -100 Standard deviation 1.7-2.4 Fe, Cu, Cu alloys, Stainless steels. Tool steels, Ni alloys, Precious metals 104-106 400 15-60 Steel iron 0.5-5 Stainless steel Cu alloys High volume, Low cost Powder purity shapeXow EE... 

In the last decade a continuously increase in the number of application fields was observed. The technical feasibility and the reliability of the materials and components were shown in many applications, such as valves and other parts for the automotive industry, bearings, household applications. For the wider penetration into the market there is a engineering work necessary to optimise the production, stabilise the reliability and reduce the production cost. First steps in this direction were made by using low cost powders and optimising processing, sintering and finishing. 

Anon., Roll-press briquetters for recycling waste sludge help steelmakers end landfdling and cut scrap costs. Powder Handling Process., 9(1), 64-67 (1997). 

Walker, K.A. (January/March 1994) Vacuum conveying to improve productivity and cut costs. Powder Handling Process., 6(1), 106. 

To prevent rejects, retouching and to reduce cost of conservatively more than enough applied powder in powder coating processes a handy measurement system allowing to determine the... 

Although benzenesulphonyl chloride has for simplicity been used in the above discussion, tolucne-/>- sulphonyl chloride, CHaCeH SO Cl, is more frequently used in the laboratory, owing to its much lower cost, the latter being due in turn to the fact that toluene-p-sulphonyl chloride is a by-product in the commercial preparation of saccharin. Toluene-p sulphonyl chloride is a crystalline substance, of m.p. 68° the finely powdered chloride will, however, usually react readily with amines in the Schotten-Baumann reaction it does not react so readily with alcohols, but the reaction may be promoted considerably by first dissolving the chloride in some inert water-soluble solvent such as acetone. 

Metal organic decomposition (MOD) is a synthesis technique in which metal-containing organic chemicals react with water in a nonaqueous solvent to produce a metal hydroxide or hydrous oxide, or in special cases, an anhydrous metal oxide (7). MOD techniques can also be used to prepare nonoxide powders (8,9). Powders may require calcination to obtain the desired phase. A major advantage of the MOD method is the control over purity and stoichiometry that can be achieved. Two limitations are atmosphere control (if required) and expense of the chemicals. However, the cost of metal organic chemicals is decreasing with greater use of MOD techniques. 

Premium 2irconia powders cost from U.S. 55 to 100/kg. Suppliers include Ferro and Z-Tech (a subsidiary of ICI) Japanese sources of powders include Toyo Soda Manufacturing Company (now Tosoh) and Daichi Kigenso. 

Tamarind kernel powder is insoluble in cold water, but upon heating forms thick viscous coUoidal dispersions at relatively low concentrations (2—3%). Upon drying, elastic films are formed. Tamarind seed polysaccharide is used as a low cost textile sizing agent in India. 

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