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A selection of commercially available chromium and chromium-free post phosphate rinses along with a deionized water rinse were evaluated over several zinc and zinc-alloy coated sheet steels. The test specimens were pretreated and electrocoated on-line in an automotive assembly plant. The effect of the rinse treatments on the cosmetic corrosion performance of the substrates, after 5 years of exposure in an outdoor scab corrosion test was determined. After this exposure none of the rinse treatments had performed better than deionized water rinse on zinc and zinc-iron coated sheet. The zinc-nickel coating showed improved scribe creepage when treated with the Cr+6/Cr+3 rinse. Data is provided comparing the concentration of the treatments used vs scribe creepage and chipping corrosion paint loss.

A comprehensive selection of automotive sheet steels were exposed in an outdoor scab corrosion test to provide a base-line of cosmetic corrosion performance. Eighteen different coated sheet steels along with CRS as a control were processed using two commercially available zinc phosphate chemistries. The phosphating was done using both immersion and spray phosphate processes in a laboratory and an automotive assembly plant. Scribe creepage results are reported for 5 years outdoor scab exposure. Comparisons of the scribe creepage behavior of CRS, zinc, and zinc alloy coatings and the effect of the phosphate treatment are provided. An estimate of 10 years field performance is made.

Resin transfer molding (RTM) is the process of choice for the Body Panels of the Viper Sports car. The objective of this paper is to outline the reasons for the choice of RTM, and discuss development of technology for Class A surfaces and the paint system. Accomplishments to date and finally the work yet to be completed will also be defined. Conclusions from the work to date indicate that the RTM process enables a reduction in vehicle development time through faster prototypes and tool build times and that high quality, Class A surfaces can be successfully achieved even with epoxy tools. Additional work is ongoing to reduce cycle times and finishing costs, and to improve the in-process dimensional stability.

Fastener failure due to hydrogen embrittlement is of significant concern in the automotive industry. These types of failures occur unexpectedly. They may be very costly to the automotive company and fastener supplier, not only monetarily, but also in terms of customer satisfaction and safety. This paper is an overview of a program which one automotive company initiated to minimize hydrogen embrittlement in fasteners. The objectives of the program were two-fold. One was to obtain a better understanding of the hydrogen embrittlement phenomena as it relates to automotive fastener materials and processes. The second and most important objective, was to eliminate hydrogen embrittlement failures in vehicles. Early program efforts concentrated on a review of fastener applications and corrosion protection systems to optimize coated fasteners for hydrogen embrittlement resistance.

With the increasing demand to improve recyclability of automobiles worldwide the Vehicle Recycling Partnership (VRP) a cooperative effort among Chrysler, Ford and General Motors has been formed. The VRP has been developing preferred practices for improvement of recyclability for future vehicle subsystems. These preferred practices are intended to assist engineers and designers in improving recyclability without impairing the performance of the subsystem. This paper discusses the practices of specific design for recycling of plastic bumper fascia systems and what the designer should consider in developing a design to improve and maximize recyclability.

The commercial validation of a optimized RRIM polyurethane substrate with a novel barrier coat for fascia applications is reviewed which creates cost competitiveness to thermoplastic olefins (TPO), without sacrificing performance. Meeting fascia performance requirements with thinner and lighter RRIM materials containing recyclate and the subsequent application of a barrier coat eliminating the traditional primecoat cycle was investigated.

A method has been employed in the stamping facility to reduce scrap by correlating observations from the press shop with laboratory test results. This paper illustrates the successful use of this method for reducing formability failures. Correlation of observed coating behavior with laboratory adherence tests is also discussed.