Compocel AL: structural aluminium sandwich panel

Compocel AL is a structural sandwich panel with an aluminium honeycomb core and aluminium skins, designed for applications where low weight, high flexural stiffness and dimensional stability are required. It belongs to the family of structural sandwich panels described in the article Sandwich panels: what they are and where they are used and represents a dedicated solution for projects based on composite materials and lightweight structures.

Its fully metallic structure allows Compocel AL to be used as a lightweight structural element, actively contributing to the mechanical and functional performance of the system in which it is integrated.

Structure, materials and technical configurations

Compocel AL consists of an aluminium honeycomb core bonded to aluminium outer skins through structural adhesive systems. The hexagonal cell geometry ensures uniform load distribution, resulting in a lightweight yet mechanically efficient panel with an excellent stiffness-to-weight ratio.

The honeycomb core is manufactured from aluminium alloys of the 3000 series and can be supplied in different configurations depending on cell size and density. Various cell pitches are available, allowing the mechanical behaviour of the panel to be tailored to the specific application.

The outer skins are made of aluminium alloys from the 1000, 3000 or 5000 series, selected according to strength requirements, workability and surface finish. Skin thicknesses and total panel thickness can be adapted to project needs, ensuring an effective balance between stiffness, weight and flatness.

This level of configurability allows Compocel AL to be used both in standardised applications and in custom-made solutions, without introducing the complexity typically associated with more elaborate multilayer structures.

Compocel AL as a structural sandwich panel

Within the aluminium sandwich panel landscape, Compocel AL is used as a lightweight structural element rather than a simple support or cladding. It is suitable for applications where the panel must maintain tight dimensional tolerances, cover large surfaces and be integrated into modular or industrial systems.

These characteristics make Compocel AL particularly suitable for sectors where weight reduction must be combined with predictable and repeatable mechanical performance, such as marine, railway, technical construction and modular systems. A representative application is illustrated in the case history dedicated to the Board modular platform, where lightness, stiffness and dimensional stability are key design requirements.

Certified version: Compocel AL FR and regulatory compliance

For applications subject to stringent regulatory requirements,Compocel AL FR is available. This version has been developed to ensure adequate fire performance in the main regulated sectors.

In the railway sector, Compocel AL FR complies with UNI EN 45545-2, achieving classifications up to HL3, the highest hazard level defined by the standard, making it suitable for interior components such as walls, partitions and lightweight flooring.

For the construction sector, the panel is classified according to UNI EN 13501-1, with reaction-to-fire classes A2-s1 d0 or B-s1 d0 depending on the configuration. This allows its use in façades, suspended ceilings, floors and technical cladding systems. In this context, Compocel AL FR has also been tested according to internationally recognised standards, including ASTM and TAS protocols, covering mechanical performance, load resistance and fire behaviour, supporting its use in projects intended for the North American market.

The panel also complies with the French standard NF P92-501, achieving M1 classification, making it suitable for applications requiring limited flame spread according to French regulatory criteria.

In the marine sector, Compocel AL FR is certified in accordance with the IMO FTP Code 2010 and is available with IMO MED certifications (Modules B and D and C bulkhead), as well as US Coast Guard approvals, making it suitable for use on passenger ships, commercial vessels and special craft.

Overall, Compocel AL FR combines structural lightness, dimensional stability and multi-market regulatory compliance, while maintaining the workability typical of aluminium sandwich panels. It is therefore suitable for projects aimed at both European and international markets.

Applications and real case references

Compocel AL is used in a wide range of technical applications, includingmarine, railway, l’technical construction, and architecture. The panel is also widely employed in outdoor applications, particularly as a façade element and architectural cladding, where lightness, dimensional stability and long-term durability are essential.

A representative example is the use of Compocel AL for the CEL Components corporate signage, described in a dedicated case history, demonstrating how the panel can be used in outdoor applications while maintaining geometric precision and high aesthetic quality.

Similarly, Compocel AL can be used as a technical backing for lightweight marble applications, especially where high flatness and dimensional stability are required, as will be discussed in the article Marble lightweighting: technical solutions with sandwich panels.

Compocel AL within the CEL Components portfolio

Within the CEL Components product range, Compocel AL represents a structural aluminium solution for advanced technical applications. It is designed for professionals already familiar with sandwich panels who are looking for a reliable, configurable product aligned with industrial requirements and international standards.