In response to ongoing pressure to reduce vehicle weight, the automotive industry has looked to replacing steel with aluminum in body structure applications. The largest barrier to this lies in the relatively high cost penalty associated withaluminum. A significant percentage of this cost penalty is related to the conversion costs of turning liquid metal into aluminum sheet. Historically, this has been accomplished by casting thick ingots of material and progressively rolling it to thinnergauges. While this technique has been the standard for many years, some attention has turned to continuous casting as a possible method of producing aluminum sheet at lower costs.In this study, two continuously slab-cast aluminum alloys have been evaluated and compared with conventional ingot cast material for possible automotive body applications. The two alloys, 5754-O and 6111-T4, were compared in terms of mechanicalproperties, formability and microstructural attributes. Additionally, three different gauges of the 5754A1 continuous cast sheet were tested in order to study the effects of sheet thickness on alloy properties. Microstructural analysis of these materialsindicated slight differences between the continuous cast and respective ingot cast alloys in terms of grain structure and dispersoid density. Although the continuous cast alloys exhibited slightly different mechanical properties than their respectiveingot east alloys, preliminary formability testing indicated only small differences between these materials. Based on the results found in this study, it appears that these continuous east alloys may become a viable alternative to conventionally-castaluminum sheet for automotive body applications.
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