Casting methods

Fig. 13. (a) The bottom-pressure casting method as appHed to slabs (b) curve mold and submerged entry no22le and (c) portion of Arvedi caster for... 

Zinc rolling slabs have been cast successfully by semicontinuous direct-chill casting methods. This is the preferred method for superplastic zinc alloys which, because of their large freezing range, display unacceptable surface shrinkage when cast in open molds. 

Comparison of Casting Methods. Table 6 compares several factors of various castiag procedures. The factors are rated A through E letter A is the most advantageous. 

In recent years rotational casting methods have made the slush moulding process virtually obsolete. In these processes an amount of material equal to the weight of the finished product is poured into a mould. The mould is then closed and rotated slowly about two axes so that the paste flows easily over the cavity walls in an oven at about 200-250°C. When the compound has gelled, the moulds are cooled and the moulding removed. Compared with the slush moulding process there is no wastage of material, little flash, and more even wall thickness. Completely enclosed hollow articles such as playballs are most conveniently made. 

The tape-casting method makes possible the fabrication of films in the region of several hundred micrometers thick. The mechanical strength allows the use of such a solid electrolyte as the structural element for devices such as the high-temperature solid oxide fuel cell in which zirconia-based solid electrolytes are employed both as electrolyte and as mechanical separator of the electrodes. 

Shaped Charge Performance for Several Casting Methods. . O... 

Ogata et al. (1997) first prepared PLA/ organoclay (OMMT) blends by dissolving the polymer in hot chloroform in the presence of dimethyl distearyl ammonium modified MMT (2Ci8MMT). XRD results show that the silicate layers forming the day could not be intercalated in the PLA/MMT blends, prepared by the solvent-cast method. Thus, the clay existed in the form of tactoids, consisting several stacked silicate monolayers. 

Shuto, K., Oishi, Y, Kajiyama, T. and Han, C. C. (1993) Aggregation structure of a two-dimensional ultrathin polystyrene film prepared by the water casting method. Macromolecules, 26, 6589-6594. 

The casting methods used in aluminum forming can be divided into three classes direct chill casting, continuous casting, and stationary casting. 

Hollow sand casting is a relatively simple process for making cast metal objects that for thousands of years was the most widely used of all casting methods. For the most basic castings, the molds are made from ordinary silica sand mixed with water so as to keep the sand particles compacted together to maintain the required hollow-shaped form. The hot, fluid... 

Immobilization of the bilayer membranes as thin solid films is required when the bilayer membranes are used as novel functional materials. Casting method is a simple way to immobilize the bilayer membrane on a solid support from an aqueous solution by drying. Polymer film is easily prepared when the cast film of polymerizable bilayer membrane is polymerized. A free standing polymer film prepared by photo polymerization of the cast film of diacetylene amphiphiles was reported by O Brien and co-workers [34]. Composition with macromolecular materials is another way of polymer film preparation. Bilayer membranes are immobilized as polymer composites by the following physical methods ... 

Wang Z, Qian J, Cao J, Wang S, and Wen TJ. A study of multilayer tape casting method for anode-supported planar type solid oxide fuel cells (SOFCs). J. Alloys Compounds 2007 437 264—268. 

Bottom-fermenting yeasts, 26 465 Bottom-pressure casting method, 23 269 Bottom-spray fluidized-bed units, 16 448-449... 

Liu, C. and Martin, G. R. 1990. Ion-transporting composite membranes III. Selectivity and rate of ion transport in Nafion-impregnated Gore-Tex membranes by a high-temperature solution casting method. Journal of the Electrochemical Society 137 3114-3120. 

Liu, C., Cui, D., Cai, H., Chen, X., and Geng, Z. (2006). A rigid poly(dimethylsiloxane) sandwich electrophoresis microchip based on thin-casting method. Electrophoresis 27, 2917—2923. 

The limitations associated with the normal casting method are ... 

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