(1) Scale formation in CSC, as well as TSC/MSC, aggravates caster maintenance. In connection with irregular Initial solidification, scale formation causes fine surface cracking, while adhering mold powder may deteriorate strip surface during subsequent rolling in a directly linked process. These problems are possibly alleviated by hard secondary cooling (<800℃ 1,472°F) and descaling prior to reheating, apart from further research in the overall scaling behavior during the continuous casting operation. (2) During reheating in the rolling mill furnace, high temperature (1,270 to 1,300℃ 2,192 to 2,372°F for low C-steel) is advantageous to decrease Cu-rich phase occurrence (in case of low quality scrap feed), as well as for easy scale washing. This is not a viable solution for TSC and MSC technologies. Therefore, more emphasis on the development of hydraulic descaling systems with high spray impact pressure (or alternative methods) is required, especially for Si-containing steels. (3) Thin transfer bars can reduce tertiary scale formation at the finishing strip mill, which necessitates the use of slab roughing. Rapid strip cooling after rolling and/or low coiling temperature for improved descaleability on the pickling line should be optimized to maintain the required microstructure and product properties. (4) The Ni-addition, which compensates for surface cracking by having an excessive Cu-content, not only increases material cost, but also impairs descaleability. Therefore, improved control of initial solidification is needed as a more direct approach to examine the cause. A Ti-addition is another potentially effective solution. (5) While all these measures are especially difficult to realize for TSC and MSC technologies, DSC with strip inertization appears to circumvent scale problems in a fundamentally sound way.
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