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The post forming performance of automotive components has continued to be an important but challenging issue in materials science and engineering. The modeling community must know the strength of the formed parts to be able to predict behavior such as crash worthiness, high cycle fatigue resistance and dent resistance. Furthermore, the ductility and toughness of the formed parts must be known for safety and warranty reasons. A review of some previous work reveals that there are levels of complexity in understanding these relationships that are often overlooked. Phenomena such as the Bauschinger Effect and compressive work embrittlement complicate the prediction of post formed properties. This is especially true when the forming strain path contains a compressive component. Previous work has shown that when a tensile stress is applied in a direction of compressive forming strain, drastic reductions in strength and toughness may result.

A newly developed tin-bearing, free machining steel, 12T14, has been evaluated at production-scale. Comparing to lead-containing 12L14 and 1215 steels, 12T14 has proven to be equal or superior in terms of machinability.

The first generation of interstitial-free or ultra-low carbon (ULC) sheet steels has good drawability but very low yield strength. The second generation of ULC steels contains high phosphorus and/or allow a partial stabilization of carbon. However, traditional alloy design does not always result in the desired properties. This paper reviews new understanding of the precipitation and mechanical behaviors of ULC steels.

The effect of calcium additions on the tool wear behavior of a series of SAE 8620 bar steels has been investigated. Of particular interest in this study was the influence of Ca additions on: (1) the stereological parameters of the non-metallic inclusions, and (2) the quantitative evaluation of the machinability behavior (B-index) of the steels using the Volvo tool wear test. The results of this investigation have revealed a linear relationship between the machinability of the workpiece (B-index) and certain non-metallic inclusion stereological parameters (ISP).