Composites can be made with or without an inner core of material. Laminated structure with a core center is called a sandwich structure. Laminate construction is strong and stiff, but heavy. The sandwich laminate is equal in strength, and its weight is much less; less weight is very important to aerospace products.
The core of a laminate can be made from nearly anything. The decision is normally based on use, strength, and fabricating methods to be used.
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