1991-02-01

Optimization of an SMC System for Maximum Surface Smoothness - GM APV Van Hood Case Study 910385

Sheet Molding Composite (SMC) technology has advanced significantly in the surface smoothness and appearance of compression molded automotive exterior body component parts over the past five years. An example of that new technology is the General Motors' APV Van Hood.
As judged visually on vehicles and measured quantitatively in the laboratory, not only by the SMC molder and fabricator, but by other SMC molders and the automotive customer, this SMC hood sets a new SMC industry standard for surface appearance for thermoset composite exterior automotive body panels.
The appearance of the GM APV Van Hood was the result of a total system approach to material and process optimization. Teamwork and partnership concepts contributed significantly and leveraged the application of technology.
Key program development factors included the evolution of new SMC materials technology, the development of methodology for the accurate quantification of surface smoothness, the development and application of new tooling procedures and standards, the characterization of press dynamic mechanical and thermal behavior, and the optimization and control of adhesive bonding and paint priming processes. The APV Van Hood program resulted from the effective integration of technical activities focused on understanding and controlling fundamental material and process interrelationships to derive controlled, capable manufacturing processes.
The end result is a high-visibility SMC exterior automotive body panel assembly with surface smoothness and appearance equivalent or better than sheet metal!
The GM APV Van Hood represents the capability and commitment of the SMC industry to be responsive to increasing customer needs and requirements, to technical innovation as a means of market growth, and to a total system approach to meeting the challenges of the future.

SAE MOBILUS

Subscribers can view annotate, and download all of SAE's content. Learn More »

Access SAE MOBILUS »

Members save up to 43% off list price.
Login to see discount.
Special Offer: With TechSelect, you decide what SAE Technical Papers you need, when you need them, and how much you want to pay.
X