Sheet Molding Compounds

Leading lightweighting in the exterior component systems

The use of Sheet Molding Compound (SMC) in the automotive industry has been steadily increasing over the past few decades. SMC is a variety of composite containing a polyester/polymer matrix with glass and carbon fibers. The composite gets its name from the specific compression molding process in which preheated sheets of the material are placed between the hydraulic presses applying around 2000 psi of force, allowing the composite to spread evenly and properly into complex shapes as required. Over time, injection molding has also been achieved for SMC leading to a faster process and more complex designs possibilities. The fibers in the SMC are generally longer than 1 inch, which provides greater strength compared to other matrix composites. This is one of the major reasons why the SMCs are used in the automotive industry, particularly for exterior component areas.