The Deformation of Clad Aluminum Sheet Produced By Direct Chill Casting
- PDF / 659,572 Bytes
- 11 Pages / 593.972 x 792 pts Page_size
- 109 Downloads / 197 Views
TRODUCTION
CLAD aluminum sheet is produced commercially by the roll bonding process; typical applications are brazing sheet in which a brazeable, usually an AlMn AA3000 series alloy, is clad with a low-melting-point AlSi AA4000 series alloy and an aerospace sheet in which a high-strength, but low-corrosion-resistant AlMgCu AA2000 or AlZnMgCu AA7000 series alloy is clad with a more corrosion-resistant dilute AA1000, AA2000, or AA7000 alloy. Roll bonding is a well-established process, but it is relatively expensive and has limited combinations of alloys that can be roll bonded successfully. Many high-strength alloys, such as the high Mg AA5000 series, are not easily bondable mainly because of their susceptibility to oxidation during the bonding process, which is carried out at elevated temperatures. Recently, a new technology referred to as ‘‘Fusion Technology’’ (Novelis–Solatens Technology Center, Spokane Valley, WA)[1,2] has been developed that produces clad material by direct chill (DC) casting. This process has few restrictions with regard to the combination of alloys that can be cast, and it allows clad sheet to be produced by essentially the same hot and cold rolling routes used for conventional, monolithic alloys. This means that in addition to brazing sheet and corrosion resistance sheet, packages can be fabricated that provide enhancement of other properties, such as improved surface properties and enhanced formability. Little information is found in the literature on the deformation of clad Al sheet, whereas many studies are available on sandwich panels and laminates that cover various aspects of deformation and fracture.[3–8] In many of these DAVID J. LLOYD, Principal Scientist (retired), and MARK GALLERNEAULT, Senior Investigator, are with Novelis Global Technology Centre, Kingston, Ontario, Canada K7L 5L9. Contact e-mail: [email protected] ROBERT B. WAGSTAFF, Director of Research, is with Novelis–Solatens, Spokane, WA 99206. Manuscript submitted October 20, 2009. Article published online May 26, 2010 METALLURGICAL AND MATERIALS TRANSACTIONS A
studies, the volume fractions of the individual components are equivalent, or close to equivalent, whereas in the clad packages of interest in the current work, the cladding volume fraction is 10 pct or less. This article examines the deformation of a clad package AA3003/ AA6000, in which the high-ductility AlMn AA3000 alloy is clad onto and forms the surface of the higher strength automotive sheet AlCuMgSi AA6000.
II.
EXPERIMENTAL DETAILS
Commercial clad sheet produced by the Fusion Technology consists of a core alloy laminated on its rolled surfaces by another clad alloy. Part of this study considers a DC ingot with a core alloy of AA6111 sandwiched between clad layers of AA3003 (each clad layer was 10 pct of the total package thickness). Sheet was fabricated via plant rolling to a 1-mm gauge after homogenizing to dissolve any coarse Mg2Si and AlMgSiCu–Q phase formed during solidification, hot rolling to 5 mm, and then cold rolling. The final gauge s
Data Loading...
