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In an effort to reduce anisotropy, which affects sheet forming performance, special actions were taken in the production of 6009-T4 sheet. To further reduce anisotropy in forming behavior, the modified 6009-T4 sheet was given an electro-discharge texture (EDT) surface topography to make friction behavior nondirectional. The modified 6009-T4 was compared to standard 6009-T4 in terms of metallurgical characteristics, laboratory test results and field forming results. The modified sheet yielded reduced planar anisotropy and improved formability. EDT completely removed directionality in friction behavior and led to an improvement in performance in the forming trials.

A program was recently conducted to study the effects of various alloying additions on the properties and performance of aluminum auto body sheet materials. As a result, a new 6XXX-series alloy has been developed which demonstrates an optimum combination of formability, strength, and corrosion resistance. This new alloy not only forms better than 2008-T4 but it can also attain strength levels during typical paint bake operations which are greater than those provided by 2036-T4, 6111-T4, and 6016-T4 as well as exhibit superior corrosion resistance relevant to all of the above mentioned materials. A patent is currently pending.

Aluminum sheet forming is entering an era where rapid advances in technology are likely. Combining increased understanding of material behavior, increased understanding of metalworking tribology and improved control of sheet forming processes will result in improved distribution of strain, allowing more complex components to be formed and greater design flexibility. New process control techniques will be developed and implemented to result in improved press actions, control of strain path to effect increased formability and reduced sensitivity to process variables. Improved techniques for assessing producibility and for generating effective tool designs will be developed, perhaps eliminating the need for soft tool tryouts to substantially reduce the total die development time and cost. In this review paper, each of these issues will be discussed.