Market Snapshot: Automotive Exteriors

Consumption of plastics and composites in North America’s vehicles rose 17% since 2000, James Best, president of Market Search Inc., confirmed in a comprehensive 2004 automotive plastics report. Today’s figures are not statistically higher, but in light of recent rising gasoline prices, future forecasts for metal-to-plastic conversions in automotive body panels are looking up.

While we currently see IM plastics employed routinely in bumper fascia, head- and taillights, doors, fenders, mirror housings, and trim, automakers may now take a harder look at the plastic potential for hoods, trunk lids, and roofs—areas that are still largely dominated by metal.

These horizontal components also bring a larger structural requirement that IM plastics meet via materials technology. For instance, the trunk lid of the Mercedes-Benz CL500 is molded from a polyamide blend compounded specifically for structural strength and creep resistance. In 2001, tier supplier Venture Industries (Fraser, MI) patented Sandwiform, a glass-reinforced polypropylene structural sandwich material, for trunk lids. Bayer’s Baypreg F sandwich composite is used in load-bearing pickup truck tonneau covers.

With resin prices also on the rise, though, the steel industry is doing its best to mount a marketing campaign aimed at taking back some of those lucrative components. Development of ultrahigh-strength, lighter-weight steels continues, along with new forming methods aimed at decreasing manufacturing costs. Plastics’ ability to compete will be based on targets such as overall lower system costs and design flexibility.

What Goes Up . . .

A two-month rapid rise in vehicle sales this summer has been balanced by August and September drops, not unexpected but still disconcerting. Reliance by automakers on employee pricing discounts made for impressive sales, but not for long-term gains. June and July saw notable gains of 7.1% and 16%, followed by a drop of 18.5% in August as the incentives expired (see graph, below).

According to Action Economics (Boulder, CO), unit vehicle sales fell by 2.5% for September to 16.3 million units. Says Mike Englund, chief economist, “September is expected to be the payback month for the outsized strength of this summer, which peaked at 20.7 million units in July.” Englund points out that inventories are now near the low end of the range seen over the last decade, a factor that limits sales growth.

Predictions for future vehicle sales through January point to a rise in demand by December to 18.1 million units, followed by a January drop to 17.3 million units. These figures are closer to the 16.8 million-unit average for the three quarters prior to Q3 2005, indicating a more stable sales landscape.

Material Trends

Other factors that will contribute to the success of IM plastics in automotive exterior applications involve resin pricing, weight savings, and design flexibility. Clear indicators of future prices for commodity and engineering thermoplastics are missing in the current environment of escalating petroleum and natural gas costs. In general, however, auto suppliers appear to be turning toward lower-cost resins to do jobs formerly owned by ETPs, or replacing steel exterior panels with plastic for lightweighting and product differentiation.

Sabic Polyolefins recently supplied a 50-50 joint venture between Toyota (Japan) and PSA (Peugeot-Citröen, France) with an ultrahigh-impact PP for bumper fascia. The Toyota/PSA group specializes in small (mini) car production, and chose the material based on a recommendation from its molding supplier, Peguform Bohemia (Kolin, Czech Republic).

The Toyota Aygo, Citröen C1, and Peugeot 107 share a lot of components, including the bumper. A combination of performance and cost convinced Toyota, which had never used PP on an exterior component, that this was the best choice for all three new “minis.” The new models appeared in Japan and France in September.

A transparent roof, standard on current Mercedes-Benz A-Class vehicles, has been selected for the B-Class models as well. Molded from a UV-resistant PC (Makrolon, Bayer), the panoramic roof is molded by Freeglass GmbH (Schwaikheim, Germany) in a two-shot process. Why replace metal with plastic? In this case, says tier supplier Webasto (Stockdorf, Germany), PC saves 3.5 kg over steel, adds design freedom, resists chipping, and won’t shatter. The roof opening also can be made 60% larger than traditional sunroofs.