A sandwich panel is any structure made of three layers: a low-density core, and a thin skin-layer bonded to each side. Sandwich panels are used in applications where a combination of high structural rigidity and low weight is required.
Sandwich panels are an example of a sandwich structured composite: the strength and lightness of this technology makes it popular and widespread. Its versatility means that the panels have many applications and come in many forms: the core and skin materials can vary widely and the core may be a honeycomb or a solid filling. Enclosed panels are termed cassettes.
Sandwich panels (sometimes referred to as composite panels or structural insulating panels (SIP) consist of two layers of a rigid material bonded to either side of a lightweight core. The three components act together as a composite; that is, the combination of the characteristics of the components results in better performance than would be possible if they were acting alone.
The lightweight core keeps the two faces in the correct position, resists shear forces, and provides insulation, while the two faces provide durability, weather and impact resistance, and resist in-plane forces of tension and compression. Sandwich panel systems include the panels themselves, the joints between them, fixings (often concealed) and a support system.