Remelt effect

The question of the remelt effect is still stressed by archaeologists who have not presented any properly discussed archaeological evidence that it was a common phenomenon in the East Mediterranean Bronze Age. 

The effects of variations in composition, cleanliness, stmcture, and mechanical properties of electroslag remelted (ESR) 35NiCrMoV12.5 steel have been reported. This steel which ties between Grades 2 and 3 of ASTM specification A723 is widely used in Europe (145). 

An alternative process is electroslag remelting (ESR). More oxide inclusions are found in ESR steel than in VAR steel, but thek size and distribution are such that they normally have no noticeable adverse effect on properties (141). 

The zinc is normally melted in a gas, oU, or coal-fired reverberatory furnace with a capacity up to 100 tons or in a low frequency induction furnace with a capacity of a few tons. The more highly aUoyed compositions are more effectively melted and mixed in low frequency induction furnaces. The furnace must be refractory-lined to eliminate iron pickup by the molten metal. The metal temperature is maintained below 500°C to minimize loss by oxidation. A ladle is used to transfer the metal for casting into molds the pouring temperature is usuaUy ca 440°C. Zinc scrap is not generaUy suitable for remelting because it may contain undesirable impurities. 

Injection molding can be used with some thermosets in addition to thermoplastics, as long as the process can be controlled such that the crosslinking or curing takes place in the mold and not in the extruder barrel. It has been used effectively, for example, with thermosetting polyester resins. Scrap runners or defective parts must be discarded, however, as they cannot be remelted. 

These granites can be generated by extreme differentiation of basaltic magmas, or by remelting mafic mantle-derived materials that have had a short residence time in the crust. Both models effectively result in the formation of new cmst and in differentiation, but as the resultant granitic magmas are isotopically primitive, it may be difficult to isolate which of the two processes was responsible for their formation. 

The foundry industry is a major player in the recycling of metals. Steel, cast iron and alirminiirm scrap can all be remelted into new products. The possible negative environmental effects of foundries result from the presence of a thermal process and the use of mineral additives. The environmental effects of a foimdry process therefore mainly relate to the exhaust and off-gases and to the re-use or disposal of mineral residues. 

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