I. Introduction to Welded Aluminum Honeycomb Panels

　　Welded aluminum honeycomb panels are metallic structural materials fabricated by using welded aluminum honeycombs as the core, clad on both sides with aluminum face sheets, and then assembled and brazed in a brazing furnace under a temperature field of approximately 600°C. In this material, all joints—between the aluminum honeycomb core and the core itself, as well as between the core and the face sheets—are achieved through metal-to-metal welding, with no non‑metallic adhesives or other such materials added. This design significantly alters the material’s properties, establishing it as an independent, novel type of metallic structural material, rather than a conventional aluminum honeycomb composite. Welded aluminum honeycomb panels offer high peel strength, excellent tensile and compressive performance, as well as outstanding resistance to high and low temperatures, non-combustibility, and strong corrosion resistance. Thanks to their integrated monolithic structure, they provide superior fatigue resistance and impact resistance, along with effective sound and thermal insulation. With zero VOC emissions and 100% recyclability, they fully comply with environmental protection requirements.

　　Due to the unique properties of honeycomb sandwich panels, they were first employed in aerospace applications, where they significantly reduced aircraft and spacecraft weight while maintaining performance, enabling longer ranges with the same fuel consumption. With continuous advances in manufacturing processes and material innovations, welded aluminum honeycomb panels have been increasingly adopted across a wide range of industries, including defense, aerospace, rail transit, shipbuilding, new‑energy vehicles, machinery, and architectural decoration. As national policies promoting environmental protection and energy efficiency gain traction, adhesive‑bonded aluminum honeycomb panels are gradually being replaced by welded versions, making the market outlook for welded aluminum honeycomb panels highly promising.

II. Technical Performance of Welded Aluminum Honeycomb Panels

2.1 High node strength

　　In welded honeycomb panels, all joints are connected via brazing. During the brazing process, the base metal does not melt, avoiding issues such as grain growth and erosion that occur in fusion welding. The weld zone between the aluminum honeycomb core support sheet and the face sheet generally forms a double-sided small‑angle weld structure, while the aluminum foil of the honeycomb core features a continuous lap weld structure along the entire edge length. In both cases, the weld area is larger than the butt joint area of the two base metals. As a result, during tensile failure, the base metal typically fractures while the joints remain intact. The roller peel strength generally exceeds 100 N·mm/mm, accompanied by a tearing failure mode of the honeycomb core. This level of performance is difficult to achieve with other joining methods.

2.2 High compressive strength

　　Welded aluminum honeycomb cores can be fabricated using thicker aluminum foil or strips. Thanks to their high joint strength and excellent structural integrity, they retain their honeycomb geometry and, even under overload-induced compressive deformation, maintain a certain load-carrying capacity without suffering crushing failure.

　　The aluminum foil thickness of the honeycomb core in welded aluminum honeycomb panels can range from 0.15 to 0.35 mm, with cell edge lengths between 0.5 and 10 mm. The compressive strength typically falls within 4 to 10 MPa; higher‑grade compressive strengths can also be achieved through specialized manufacturing processes.

2.3 Tensile Strength

　　Because the aluminum honeycomb panel’s face sheets and core are integrally bonded, its tensile strength is significantly enhanced; with a cell size of 4 mm and a wall thickness of 0.1 mm, the core can achieve a strength exceeding 6 MPa.

2.4 Excellent temperature and corrosion resistance

　　All materials used in welded aluminum honeycomb panels are pure aluminum alloys, and no non-metallic materials are added during the entire manufacturing process. The forming process is carried out at temperatures as high as 600°C, giving this material excellent thermal resistance. Moreover, due to its monolithic aluminum alloy structure, the welded aluminum honeycomb panel exhibits outstanding corrosion resistance; according to ISO 9227, after a 168-hour neutral salt spray test, no visible corrosion was observed.

2.5 High fatigue life

　　In welded aluminum honeycomb panels, the face sheets and the aluminum honeycomb core are joined together by welding, resulting in a high fatigue life. Resulting in excellent fatigue life. According to third-party fatigue testing—conducted with a load of F = 1.8 ± 0.5 kN applied at the center and a frequency of 10 Hz—the product exhibited no cracking or deformation after 3 million cycles.

2.6 Good impact resistance

　　In accordance with IEC 61373, the product underwent a vibration test lasting five hours in each of three directions—vertical, horizontal, and longitudinal—at frequencies ranging from 5 to 150 Hz, and exhibited no cracking or deformation.

Table 1: Conditions for the Long-Life Simulation Test

2.7 Excellent sound and thermal insulation performance

　　Welded aluminum honeycomb panels exhibit excellent sound‑insulating and thermal‑insulating properties, with a thermal transmittance of 5.36 W/(m²·K). Their weighted sound reduction index and spectrum correction values are: RW(C;Ctr) = 26 (0; −3) dB, it offers excellent sound and thermal insulation properties. Moreover, these panels are resistant to high temperatures and corrosion, making them suitable for use in a wide range of harsh environments.

2.8 Smokeless and non-toxic

　　Welded aluminum honeycomb panels are made of pure aluminum alloy, a structural material that contains no organic compounds or other substances, and do not release any toxic or harmful substances.

2.9 Lightweight

　　The welded aluminum honeycomb panel has an area density of 8–10 kg/m² and a bulk density of 0.4–0.5 × 10³ kg/m³, giving it a lower overall density compared to other types of honeycomb panels.

2.10 Environmentally friendly and recyclable

　　The honeycomb core and face sheets that make up the welded aluminum honeycomb panel are both made of aluminum alloy. The brazing filler metal is a Series 4 hard aluminum alloy, which is pre-rolled onto the aluminum sheet surface through physical rolling. No toxic or hazardous substances are added or generated during the production and forming process of the welded aluminum honeycomb panel. The product is a pure aluminum alloy structure and is 100% recyclable. Therefore, the entire production chain—from raw material preparation to product manufacturing to product recycling—is a pollution‑free and recyclable process.

III. Applications of High-Strength Welded Aluminum Honeycomb Panels

　　At present, the domestic market for honeycomb sandwich panels is quite robust; however, products manufactured using conventional adhesive bonding suffer from aging and limited fire‑resistance. With continuous advances in manufacturing processes and material innovations, welded honeycomb sandwich panels are increasingly being adopted across a wide range of industries, including defense, aerospace, rail transit, shipbuilding, automation machinery, and architectural decoration. Annual market demand stands at approximately 2 million cubic meters, and this figure continues to grow year by year in response to expanding industrial needs.

　　In the defense industry, this material can be used for emergency runway pavement panels, modular shelters, bunkers, missile launch canisters, radome housings, and more.

　　In the rail transit sector, this material can be used for vehicle underbody panels, equipment compartment covers, vehicle floors, interior roof panels, door systems, and more.

　　In the construction sector, this material can be used for decorative exterior walls, interior home finishes, toilet partitions, high-end furniture, and more.