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In this work, the application of the split sleeve cold expansion process on different aerospace aluminum alloys was investigated. The study was undertaken for a number of aluminum-lithium alloys in order to provide a recommendation for material / process optimization. The results showed that, in general, these materials can undergo this process without cracking in severe but realistic conditions. In addition, in order to apply the process for the most difficult cases, the performance of a new sleeve design was investigated on a 7085-T7651 aerospace aluminum alloy plate. Although the new design was not optimized, experimental evidence showed that it can significantly reduce cracking near a sleeve split.

This paper presents the results of an investigation into the material variables that influence the weldbonding of aluminum. The four major variables that were considered in this study were the aluminum alloy, type of adhesive, the presence of a forming lubricant, and the metal surface treatment. To maximize the amount of information gained from this study, a statistical design of experiments was used. The particular design used here is an example of a screening design, in which a relatively small number of variable combinations is investigated to identify those variables that have a strong impact on the measured responses. The responses in this experiment consist of both quantitative measurements and qualitative judgments that must be taken together to interpret the experimental results. The “quantifiable” responses included weld parameters (current and percent heat); nugget diameter; weld quality ratings (based on a subjective rating system); and tensile strength.

Increasing use of aluminum in automotive components has led to lower fuel consumption and enhanced performance of automotive designs. From a manufacturing standpoint, aluminum provides the additional advantage of utilizing same processes as steel. Performance and durability of painted aluminum cars, however, is dependent on proper optimization of process conditions. As part of an extensive study of factors influencing corrosion resistance of painted aluminum, the present study deals with the influence of pretreatment and coating variables and the interaction of alloy composition with zinc phosphate and electrocoat. Interfacial analysis of corrosion products indicates the relative influence of alloying elements on stability of the metal/phosphate/electrocoat interface. As a result, guidelines and recommendations on aluminum processing in an automotive manufacturing floor have been developed.

This work describes a sheet forming process simulation, cup drawing and redrawing, using a new plane stress anisotropic yield function that describes the anisotropic behavior of aluminum alloy sheets well. The anisotropy of the function was introduced in the formulation using only linear transformations on the Cauchy stress tensor or deviator. The implementation of this constitutive equation in finite element codes was briefly explained. Simulation results were presented and compared with experimental data.