Steel-Polypropylene-Steel Laminate – A New Weight Reduction Material

In the next five years, the weight of the average car will be reduced from 3350 lb (1521 kg) to 2900 lb (1317 kg) to meet the 1985 fuel economy standard. Extensive material substitutions will be needed to achieve this projected weight reduction. To help achieve this weight reduction, a steel-polypropylene laminate consisting of two outer skins of steel with a core of polypropylene is being developed. This laminate has the potential to reduce component weight by 50% with no loss in flexural stiffness. This paper characterizes the dent resistance, flexural stiffness, fatigue strength and formability of this laminate for automotive applications. Many of the above properties are comparable to those of steel.