The most common types of core materials used in composite sandwich structures fall into three main categories: foam cores, honeycomb cores, and natural core materials.
Foam core materials are the most widely used. Examples include PVC foam core, PET foam core, PMI foam core, PU foam core, and SAN foam core. These materials are lightweight, easy to process, and compatible with many composite manufacturing processes such as vacuum infusion and resin transfer molding.
Honeycomb core materials are another important category. These cores consist of a hexagonal cell structure that provides excellent stiffness-to-weight performance. Popular options include polypropylene honeycomb, aluminum honeycomb, and aramid (Nomex) honeycomb.
Natural core materials such as balsa wood are also widely used, especially in wind energy and marine applications. Balsa offers high compressive strength and good bonding characteristics with composite skins.
Each core material type is selected based on required properties such as weight, strength, cost, temperature resistance, and environmental durability.
