Road traffic signs are the core visual carriers for the safe operation of road networks. Among them, circular prohibition and instruction signs are the most widely used sign format in global road networks due to their high recognizability. The performance of their substrate directly determines the retroreflective stability, outdoor service life, and maintenance costs of the signs. Haomei Aluminum has deep expertise in the export of aluminum materials for traffic facilities. Addressing the complex outdoor service conditions of road signs—strong ultraviolet radiation, high humidity, windy conditions, and large temperature fluctuations—Haomei has developed a full range of aluminum circles specifically for road signs. The road sign aluminium circle replace traditional galvanized steel substrates, effectively solving industry pain points such as easy corrosion, heavy weight, and poor adhesion of reflective film. They are fully adaptable to the production needs of various circular traffic signs in municipal roads, highways, industrial and mining parks, ports, and airports.

Unlike civilian-grade processed aluminum materials, aluminium circles for road signs have clear engineering-grade performance thresholds.
Firstly, the flatness and structural rigidity of the board are crucial. Circular signs are subject to wind loads and temperature variations over long periods. Insufficient flatness of the substrate can easily lead to board warping and wrinkles in the reflective film, directly weakening nighttime retroreflective visibility. Therefore, the substrate must have stable semi-rigid mechanical properties and exhibit no significant deformation during long-term service.
Secondly, weather and corrosion resistance are essential. The board must withstand acid rain, coastal salt spray, and industrial exhaust gas corrosion to prevent pitting and rust spots that could cause the reflective film to peel off.
Thirdly, surface adhesion is critical. The surface roughness and passivation film layer must match the bonding requirements of engineering-grade and high-intensity reflective films to ensure a strong bond and prevent air bubbles or peeling.
Fourthly, lightweight and easy processing are important to reduce the difficulty of high-altitude installation and subsequent maintenance.

Based on the performance requirements of different working conditions, the signage industry has established a clear grade selection system. For general municipal road applications, 1060 H14 aluminum circles are commonly used. The base material has an aluminum content of ≥99.6%, moderate semi-hard tensile strength, excellent surface flatness, and a standard thickness of 1.0mm-2.0mm. They can cover mainstream national standard circular sign sizes such as φ600mm and φ800mm, offering excellent overall cost-effectiveness and making them the first choice for small to medium-sized municipal projects. For coastal areas with high salt spray, corrosive industrial environments, and large-diameter signs on highways, 3003 H14 aluminum-manganese alloy circles are preferred. After manganese alloying, the material's corrosion resistance is increased by more than 40% compared to pure aluminum, resulting in higher structural strength and stronger resistance to strong wind deformation. They are suitable for large-size prohibition signs of φ1000mm and φ1200mm, extending outdoor service life by 3-5 years.

Haomei Aluminum's road sign aluminium circles are manufactured strictly in accordance with ASTM B209 International Aluminum Standards. Standard sign sizes are readily available, and non-standard diameters and thicknesses can also be customized upon request. The aluminium circles are manufactured using a high-precision rolling process, with a flatness of ≤0.5mm/m and no burrs or flash on the edges. They can be equipped with chromium-free passivation or anodizing surface treatments, achieving a reflective film adhesion level of 0, and showing no significant corrosion after over 1000 hours of salt spray testing. The entire product line features double-sided protective film coating, suitable for ocean shipping and warehousing needs. Leveraging stable batch quality control and delivery capabilities, we have become a core aluminum supplier for transportation engineering clients in many countries worldwide, helping them improve project delivery quality and reduce the overall lifecycle maintenance costs of signage.