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Twin roll strip casting of aluminum alloy A7075 using commercial scale machine was operated. Twin roll casting process is able to produce a strip from molten metal directly. Thus this process has a possibility to reduce total cost of sheet making comparing to conventional rolling process. Strip casting process has some disadvantages. Casting speed depends on the material properties. It is difficult to determine the casting conditions. Aluminum alloy A7075 has high tensile strength, and it is known as a material for aerospace application. The sheet is manufactured in small quantities comparing to the other sheet aluminum alloy. It is supposed that the demand of high tensile strength aluminum sheet such as A7075 is going to increase for weight saving of structural material. The aims of this study are to investigate the effect of roll speed on the strip. Strip could not be produced continuously at roll speed of 10 m/min, so the load limit of this experimental apparatus was exceeded. However, a good strip without cracks was produced. Continuous strip was produced at a roll speed of 20 m/min. The strip was consisted of a mat part and a metallic luster part. However, cracks were observed in the white mat part of the board. Continuous strip was produced at a roll speed of 30 m/min. However, rolling cracks were observed at the edges of the strip. It is necessary to control the solidification distance by installing the nozzle.

This paper describes a vertical type twin roll strip casting process for producing aluminum alloy strip of ADC12, A3003 and A7075. Twin roll casting process is able to produce a strip from molten metal directly. Thus this process has a possibility to reduce total cost of sheet making comparing to conventional rolling process. Aluminum alloy ADC12 is a casting material that is used for die casting. A3003 is known as a wrought aluminum alloy for aluminum can body sheet. The A3003 sheet is generally produced by rolling, so it is effective for reducing a process cost to produce the strip by twin roll casting process. Aluminum alloy A7075 has high tensile strength, and it is known as a material for aerospace application. The sheet is manufactured in small quantities comparing to the other sheet aluminum alloy. It is supposed that the demand of high tensile strength aluminum sheet such as A7075 is going to increase for weight saving of structural material. In this study, twin roll casting experiment was performed to produce these three aluminum alloy strip in same experimental conditions. Castability, surface conditions and strip thickness were estimated. It was possible to cast these aluminum alloy strip.

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