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Strip cast AA5754 sheets are of interest for automotive interior panel applications. However, Portevin-Le Chatelier (PLC) bands are seen in this material and cause surface quality concerns. Moreover, shear banding is the main failure mechanism of this material. However, the relationship between PLC bands and shear bands is still controversial in the literature. In order to delineate this problem, the digital image correlation (DIC) strain mapping technique is used to explore the three-dimensional structures of PLC bands and shear bands in AA5754 sheets. Two-dimensional DIC measurements were carried out simultaneously on both of the sheet sample surfaces (front and back side) of an AA5754 tensile sample using a commercially available optical strain mapping DIC-based system (Aramis). DIC measurements were also conducted on the thickness direction. Based on the strain mapping results, the three dimensional structures of both PLC bands and shear bands are constructed.

A new core binder system (1) was used to produce foundry cores for casting hollow aluminum suspension parts by the low pressure, gravity flow, semi-permanent mold method. These and other prototype aluminum parts made using the system demonstrate that easy core removal from complex castings, core and sand recycling, and an improved environment in the core making facilities will increase productivity, improve product quality and reduce manufacturing costs.

We have studied the formability of continuous strip cast (CC) AA5754 aluminum alloy for automotive applications. Strip casting technology can considerably reduce material cost compared with conventional direct chill (DC) cast aluminum sheets. However, the CC material tends to exhibit much less post-localization deformation and lower fracture strains compared with DC sheets with similar Fe content, although both alloys show similar strains for the onset of localization. Bendability of the CC alloy is also found to be inferior. The inferior behavior (post-necking and bendability) of the CC alloy can be attributed to the higher incidence of stringer-type particle distributions in the alloy. The formability of the AA5754 alloy has also been studied using two dimensional microstructure-based finite element modeling. The microstructures are represented by grains and experimentally measured particle distributions.

ACuZinc™ 5, a GM-patented, high-performance ternary zinc-copper-aluminum alloy which is suitable for manufacturing net shape die castings, plays a vital role in the success of new automotive parts and systems. The new parts were designed to meet the auto industry's higher load and safety specifications. The superior mechanical properties of ACuZinc™ make it suitable for structural applications where commercial zinc die casting alloys have been found to be inadequate. From a business viewpoint, ACuZinc™ can help in penetrating new markets by competing for cast iron, powder metal and brass applications. ACuZinc is a registered GM trademark.