Abstract
Today, the progress in aluminium production takes place within strong competition in the global market that demands a continuous increase in the efficiency of the final product. With the steel industry currently going through a crisis, the main vector of development in the aluminium industry in recent years is an increasing share of high value added products. The most popular product in the global aluminium market is aluminium alloys used to produce ingots, rolled products, sections and packing materials which entirely meet the requirements of end consumers. Production of slabs from 1ХХХ series aluminium alloys meant for the foil industry is one of the potential projects realized by the leading Russian aluminium producer OK RUSAL. At the same time the existing production techniques cannot offer stable quality of the internal aluminium slab structure. Heavy 1ХХХ series ingots experience internal defects of an inhomogeneous structure which affects the quality of the foil. The major defects in foil production related to inhomogeneous structure include floating crystals and fan and fir-tree structures. Based on the analysis of technical literature and experimental data acquired in a real-life production environment, the authors offer their recommendations on the best process parameters for heavy 1ХХХ series ingot casting, ensuring the absence of such defects as floating crystals, fan and fir-tree structures.
Keywords
1XXX series aluminum alloys, heavy ingots, structural defects, fan and fir-tree structure, “floating” crystals.
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