There are about as many members in this family as there are in the foam family of materials, and just as you might expect, the differences between them are rather wide. Most honeycombs are a nested array of hexagonal cells, made from any one of the many standard papers, woven fabrics, plastic or metal foils. Many non-hexagonal honeycombs have been used commercially, but the hexagonal cores exhibit both higher strength and a better balance of properties than most other configurations.
Most common problems relating to aluminium honeycombs and their use in composite structures is the difficulty of adhering facings to the thin edges of metallic honeycomb with very little surface area, Good adhesive properties are required, that surpass that of most polyester based resins. Additionally, high process temperatures are required to effectively use epoxy based with metallic honeycombs. Another drawback of metallic honeycombs is its corrosion resistance in marine environment and the high thermal conductivity (no insulation value).
Nidaplast (Nida-Core) has a semi porous plastic membrane and a scrim that is heat welded to the honeycomb that eliminates the bonding problems of most honeycombs. The cells are constructed in Polypropylene and will not corrode and has a low heat transfer rate (K = 0.03). The elastic property has many advantages. The sound transfer through Nidaplast will be far less than a foam or a balsa core. It will handle impact with lower catastrophic failure than other cores. It shows a low shear modulus due to the elastic properties, and is often un-fairly overlooked when using shear modulus as a benchmark. As with the foam scenario, the polypropylene honeycomb has relatively low softening temperatures and requires careful consideration in SA sun (no dark colours). As a positive spinoff, thermoforming can also be done with Nidaplast.
We supply Nidaplast in various thicknesses in sheets of 1.22m x 2.13m from 5mm to 50mm. Virtually any non standard or non stock thickness is available to order, but this is subject to a minimum order quantity, as well as requiring manufacture and delivery time.