How Smart Mandrels Work

Smart Mandrels are reusable mandrels created to reduce the complexity and hassle of the composite tooling process. With this ground-breaking technology, commercial filament winders and composite manufacturers now have access to an inexpensive solution to the high labor and materials costs normally associated with trapped tooling.

CRG has invented fully cured, high-performance thermoset systems (Veriflex) that are elastic above set transition temperatures and recover to a "memory" shape when left unrestrained. Mandrels made with these thermoset systems provide distinct advantages over conventional approaches. Veriflex mandrels can be easily molded, extracted, and reused.

Advantages of Shape Memory Properties

When heated above the transition temperature, the mandrel becomes elastic and can easily be molded into a desired shape. Once cooled, the material will become rigid and retain the new shape. The mandrel can then be filament wound and the resulting part cured on the mandrel. Heating the mandrel above its transition temperature after the part is cured makes the mandrel elastic again and easily extractible from the part. Because of the mandrel's shape memory properties, it can be returned to its original tubular shape and reused.

Benefits of Using Smart Mandrels

• Faster fabrication process, reduced cycle time
• Reduced material and mandrel creation costs
• Reduced labor costs
• Simple extraction process
• Reusability
• Lower environmental impact, cleaner process
• Tremendous shape versatility

Current Characteristics

Transition temperature................85 °C
Cure temperature of part
    Mandrel process......................up to 40 °C
    Bladder process......................up to 140 °C
Demold temperature...................up to 130 °C

Comparison with Conventional Tooling

Step 1: A shape memory polymer Smart
Mandrels mandrel.