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Recent developments in composite technology offer improved performance at lower costs. The key to successful design optimization is specifying the proper combination of reinforcement fiber/fabric, matrix resin, and manufacturing process. Designers who traditionally designed with metal and plastics, have found that a basic familiarization with the mechanical behavior of different fiber and resin combinations, enabled them to optimize designs using several technologies synergistically. The general subject areas of this paper are basic composites, reinforcing fibers and fabrics, manufacturing methods, and product engineering for value.

The development of a low cost, high production thermoformable fabric composite required a new approach to traditional resin systems. An epoxy resin was developed that allows the composite piece to be thermoformed. The material, supplied in cured board form, can be reshaped at temperatures less than 200C (392F) with only the application of vacuum pressure. This allows the user to design light weight, high strength composite structures without the normal processing constraints associated with traditional composite structures. The driver behind the product development was an existing commercial application where material utilization and processing times were key factors to the success of the product. By prefabricating a cured flat sheet, net size parts can then be cut out with a waterjet, and the pieces are then thermoformed into their final shape.

Honeycomb absorbs energy by crushing under load. This characteristic has proven to be one of the most reliable and efficient methods of providing “G” limit protection. The action of crushing develops a uniform level of stress near the optimum response desired for energy absorption materials. Energy absorbing designs using honeycomb are presented in several forms. This paper presents a rapid method for calculating preliminary solutions for “G” limit protection. Honeycomb has had application as a calibrated “G” load limiter in test carts and in production steering columns and knee bolsters. Recently a method for continuous production of honeycomb materials from polypropylene and polyethylene (DuPont Tyvek®) called CECORE™ has been developed. These materials are very lightweight with a range of crush strengths and applications. This allows designers to use recyclable base materials in configurations proven to manage energy.