Casting temperature

Although more and more zinc sheet and strip are produced in continuous mills, some is stiU produced by rolling slabs cast in open or closed book-type molds made of cast iron (124—127). The casting temperatures are between 440 and 510°C, mold temperatures between 80 and 120°C. The contact surfaces of the mold must be smooth and clean to allow unrestricted shrinkage of the cast slab. Mold lubricant is not necessary, but if used should be held to a minimum. Slabs cast in open molds must be skimmed immediately to remove surface oxide. Rolling slabs are cast 1.87—10 cm thick. 

Value given is at room temperature. Value in parenthesis is at casting temperature. Value given is minimum value. 

These are alloys containing more than 50% of copper used to overcome the softness, low tensile strength and high casting temperature of the pure... 

Pentolites are castable expl mixts containing PETN and TNT. The most commonly used blend consists of 50/50 PETN/TNT, but other blends such as 75/25, 40/60, 30/70 and 10/90 have been occasionally employed. Molten TNT dissolves appreciable amounts of PETN as shown in Fig 1. The eutectic in the TNT-PETN system occurs at 76.7° for a 87/13 TNT/PETN mixt. Because correspondingly more PETN than RDX dissolves in TNT, the viscosity of Pentolites at casting temperatures is less than that of comparable Cyclotols (RDX/TNT blends)... 

The mold containing the polyurethane should be placed in an oven that is set to a temperature 5 to 10°C higher than the casting temperature. The ideal temperature is the maximum the molding will reach. This will reduce the shrinkage in the mold. 

The size and shape of the article will also affect the temperature required. A sphere may require a lower casting temperature to prevent overheating in the center. 

The gel with a concentration higher than 60 wt % showed a broad transition and the transition was irreversible. The solid film has the structure of form A reported by McKinnon and Tobolsky They have reported that films cast from DMF have two solid state modifications (form A and B) depending on the casting temperature,... 

Formation of concentration gradient should depend on (a) dissolution rate of PVC in PMA solution, (b) diffusion rate of PVC in PMA solution, and (c) interruption time of the diffusion due to completion of solvent evaporation. Factors for controlling the above phenomena are (1) type of solvent, (2) casting temperature, (3) molecular weight of PVC, and (4) amount of PMMA solution. 

In the casting of some metals, for example, iron or steel, very high casting temperatures are involved, that is, 2500-2900°F. If the mass of the core is small relative to the mass of the cast metal during such high temperature casting, there may be some vitrification of the silicate... 

Total hardness (natural hardness - - age hardening) of Pb—Sb alloys. Cast temperature 500 °C,... 

Grain refinement of Pb—2.5 wt% Sb chill cast battery grids by means of Se and S additions. Casting temperature 500 °C, mould temperature 135 °C [34]. 

As far as we know, the process of crystallization of low molecular weight substances in polymer matrices has not been studied until now. This problem is complicated because, as is usually the case with multicomponent systems, many factors affect this process. Moreover, small amounts of crystallites in the polymer matrix make most of the direct structural investigation techniques inapplicable. The casting temperature, the properties of the polymer matrix and of the solvent influence the crystallization process and the resultant morphology of the CT complex. On the basis of the results obtained we discuss the conditions which should be fulfilled to obtain low resistivity of the polymer-CT complex systems. 

The cast temperature has significant influence both on the quality of the obtained polymer films and on the crystallization... 

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