What are the common materials used to make honeycomb panels?
honeycomb panels
Honeycomb panels are sturdy lightweight building materials often used in exterior cladding. They are a type of sandwich material consisting of cells that can be either hexagonal or arranged in columns.
Honeycombs can be made from many different materials, but aluminum honeycomb is the most commonly used due to its advanced strength, stiffness and corrosion resistance. It is also relatively easy to form into flat or curved panels. It is used in a variety of industries including construction and transportation.
It is a common choice for use in aircraft and railway applications where it can help save energy and reduce the weight of the structure, which helps lower fuel consumption and carbon emissions. It can be bonded to various skins, such as fiberglass and Formica, as well as other solid surfaces, and is compatible with a variety of structural adhesives including epoxy resins.
What are the common materials used to make honeycomb panels?
Depending on the application, the honecomb panel can be filled with rigid foam to provide a better bond area between the core and the skins, improve the mechanical properties of the core and increase acoustic and thermal insulation. The core can be made from a wide range of materials, such as polypropylene, which is noted for its toughness, extreme chemical resistance and elongation. This honeycomb can be thermoformed or vacuum bagged in place, which eliminates the need for scoring, preventing excessive resin uptake and cosmetic or structural defects.
Another common type of honeycomb is Nomex honeycomb, which is created from a meta-aramid paper dipped in thermosetting phenolic resin and has excellent fire resistance. This is used in aircraft interior panels, as it provides high strength and good fire resistance in conjunction with phenolic resins on the skins. Special grades are available for use in marine-related applications that require fire retardant and high strength properties.
The most common method for fabricating honeycomb is by adhesive bonding flat sheets of the material with offset lines of adhesive and then expanding it to the desired thickness. The expanded honeycomb can be either Hexagonal or rectangular in shape, with properties dependent on the geometry of the cell and the material of the core. A bell-shaped core (also known as flexcore) has curved cell walls that make it extremely flexible along the ribbon direction and moderately flexible in all other directions. This is useful in structures with complex curves. An overexpanded honeycomb is a more rectangular-shaped core that is made by expanding the sheets more than they are needed to make hexagons and is very flexible perpendicular to the ribbon direction.
Before applying an adhesive to bond the honeycomb panel, the surface should be cleaned thoroughly with a solvent such as IPA to remove any dirt or oil. This will help ensure a strong and long-lasting bond. For best results, the adhesive should be a two-component thixotropic toughened paste that cures at room temperature and offers high lap shear, peel and shear strengths as well as gap filling and non-sagging up to 10mm thick.