Author: Ali Reza Eivani, Jie Zhou, Jurek Duszczyk
Company: Iran University of Science and Technology, Delft University of Technology
Issue #: Vol. 70, No. 3
Year: 2012
Pages: 6
Description:
Extrudability is customarily defined as the maximum extrusion speed for a sound extrudate with sufficient dimensional and shape accuracy. In the case of medium- and high-strength aluminum alloys for transport applications, however, an appropriate microstructure is also required. In other words, undesirable, localized microstructure changes, such as a peripheral coarse grain (PCG) structure, formed in the subsurface layer of an extruded product that result in performance nonuniformity may make it disqualified for transport applications. This review article intends to redefine the extrudability of the 7xxx series aluminum alloys (with Al-4.5Zn-1Mg alloy, AA7020, taken as a representative) and to provide viable solutions to solving the PCG problem without any sacrifice in productivity, for example, through alloying and applying an optimized homogenization treatment.
Product Code: art-00357