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Corrosion resistance has been the major impetus toward increased use of galvanneal and other coated sheet products by the automotive industry. Galvanneal has the additional advantages of good weldability, due to the iron in the coating, and a higher surface porosity which leads to better paint adhesion. The porosity of the galvanneal surface, however, could also lead to reduced cleanability. This paper reports the effects of pretreatment variables on galvanneal phosphatability and resulting painted corrosion performance. The studies showed that the rust preventative oil applied and the alkaline cleaner used to clean samples prior to phosphating had significant effects on carbon residuals after cleaning. The painted corrosion performance of galvanneal panels with various levels of residual carbon showed a much smaller effect within a given cyclic test. The studies also indicated significant differences in performance depending on the type of cyclic test performed.

An extensive investigation was conducted to assess the influence of steel sheet surface finish (i.e. topography or “texture”) on painted surface appearance. Ten sets of steel panels representing a variety of shot blast, EDT, laser, and bright surface textures were painted simultaneously using advanced solvent-based luxury vehicle paint systems. Paint appearance was measured using a relatively new Autospect instrument and also in terms of conventional Distinctness of Reflected Image (DOI). The results are discussed in detail with respect to 1) the influence of different steel surface textures on paint appearance, 2) the evolution of surface topography during painting, and 3) the implications of this work.

Product Engineering, Component Supply and Vehicle Assembly are the main forces that transform ideas, customer research and technical information into products. Quality professionals, and others, have advanced many concept models about improved Product and Process Development based upon the application of new tools and systems to Engineering, Procurement/ Supply and Manufacturing/Assembly relationships. Regardless of the concept model, the problem of effecting operating change in U.S. automotive business practices has both behavioral and technical implications. While many studies have emphasized the application of quality tools and systems as a means to improve Product/Process development, they often overlook the cultural change that is necessary to transition from a 75-year history of strong vertical organizations to the “Networking” implicit with new concept models. The availability of improved tools and systems alone will not insure behavioral change.

Forming Limit Diagrams (FLD) are extensively used in North American press shops during tooling trials and in production for problem identification/resolution. The Keeler-Goodwin FLC shape and the correlation developed by Keeler and Brazier (based on n-value and thickness) have been widely accepted as the Standard FLC Method to predict forming limit curves for commercial steels. In this paper, the Standard FLC Method is reviewed, and an alternative approach used at the authors' laboratory (Bethlehem FLC Method) is described. The two methods are discussed in the context of more recent experimental determinations of FLC's for a variety of “modern” sheet steels including DQSK, Interstitial Free and Bake-Hardening steels, as well as coated sheet products. Some specific press-shop examples are also presented, which further highlight the value to industry of re-examining the Standard FLC Methodology used in circle-grid analysis.

The increased use of a wide variety of recently developed engineered materials and associated processes, for producing vehicular components, has posed a significant challenge to those charged with the responsibility of knowing, developing and/or applying inspection and testing technology to support the quality assurance of these materials, processes and resulting products. This challenge can be more easily and effectively met, within the constraints of time, expertise and other available resources, if computerized knowledge-based systems are employed to enhance the identification, acquisition and application of advanced inspection technology. This paper provides an overview of developments underway to implement this approach in an automotive environment.

Since 1985, the Body Division of the Automotive Corrosion and Prevention Committee of SAE (ACAP) has conducted biannual surveys of automotive body corrosion in the Detroit area. The purpose of these surveys is to track industry wide corrosion protection improvements and to make this information available for public consumption. The survey consists of a closed car parking lot survey checking for perforations, blisters, and surface rust. This paper reports the results of the five surveys conducted to date.

The scope of Finite Element Analysis in the Product Development Cycle is given. A brief review of the development process is given. A brief description of the analysis method is presented. A description of how it works, how is it implemented, and where do I use it are included. The entire range of questions are answered through, how do I train for it, how do I manage it, along with what are the limitations and what are the benefits of this analysis method.