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Aluminum alloys are increasingly utilized in automotive body panels and crash components to reduce weight. Accurately assessing formability of the sheet metal can reduce design iteration and tooling tryouts to obtain the desired geometry in aluminum stampings. The current ISO forming limit curve (FLC) procedure is a position dependent technique which produces the FLC based on extrapolation at the crack location. As aluminum sheet metal use increases in manufacturing, accurate determination of the forming limits of this material will be necessary prior to production. New time dependent methods using digital imaging correlation (DIC) account for variations in material behavior by continuously collecting strain data through the material necking point. This allows more accurate FLC determination that is necessary for efficient design in the automotive stamping industry.

Friction stir welding (FSW) is a new welding process developed at The Welding Institute in Cambridge, U.K. This process uses a non-consumable rotating third body to generate frictional heat and create forging to facilitate continuous solid-state joints. In this paper, the current state of the art of FSW is discussed. A preliminary description of the process is provided, followed by the results of some relatively simple thermal modeling. The modeling results are used to provide a description of temperature distributions in FSW, as well as illustrate the effects of variations in process conditions. Representative microstructures of FSW on an Al 6061 alloy are then presented. Properties of these friction stir welds are then discussed and compared to those of both the base metal and to comparable GTAW welds. Some discussion is then given to the effects of section thickness on FSW. Examples are given of friction stir welds on aluminum alloys ranging from 2 to 30 mm in thickness.