Microstructure, mechanical properties and texture of an AA6061/AA5754 composite fabricated by cross accumulative roll bonding

• Published in: Materials science & engineering. A, Structural materials : properties, microstructure and processing Structural materials : properties, microstructure and processing, 2015-07, Vol.640, p.235-242
• Main Authors: Verstraete, K., Helbert, A.L., Brisset, F., Benoit, A., Paillard, P., Baudin, T.
• Format: Article
• Language: English
• Subjects: Aircraft components; Aluminium alloys; Aluminum base alloys; Automotive components; Condensed Matter; Cracking (fracturing); Cross accumulative roll bonding; EBSD; hot cracking; Materials Science; Mechanical properties; Microstructure; Physics; Roll bonding; Surface layer; Texture
• ISSN: 0921-5093; 1873-4936
• DOI: 10.1016/j.msea.2015.05.106

AA6061 alloy is a widely used material in the automotive and aerospace industries, but is prone to hot cracking, which limits its weldability. To prevent this phenomenon, the AA6061/AA5754 composite was formed using a severe plastic deformation technique, Cross Accumulative Roll Bonding (CARB), at an elevated temperature (350°C) to ensure good bonding between layers. This technique was efficient to maintain a small grain size, even under the process temperature conditions, and consequently, preserve good mechanical properties. The composite had better mechanical properties than the initial aluminium alloys. Microstructure and texture remained stable after two cycles and yield stress tended towards an equal value in the rolling and the transverse directions. After two cycles, the main component was the {001}〈110〉 rotated Cube, which was maintained for up to 10 cycles. Diffusion was more effective as the strain increased. Finally, a tungsten inert gas (TIG) welding process was performed on the composite and confirmed resistance to hot cracking.