Phenolics creep up on engine applications

Twenty years ago, the OPEC oil embargo jarred automakers into designing with a new emphasis on weight reduction to improve fuel efficiency. Polymer composites are frequently selected because they reduce costs, corrosion, noise, and heat transfer. Although phenolic thermoset composites reinforced with 30 to 40 vol% glass fibers are only half as strong and a quarter as stiff as aluminum, moldings of these materials offer substantially better dimensional accuracy and repeatability than aluminum die castings. Compared with other thermoplastic and thermoset composites, they offer superior stiffness and creep performance. These attributes make phenolic composites suitable for a variety of load-bearing engine and transmission components.