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RAL 9007 gray aluminium sheet, a classic color in the industrial metal materials field, has established a mature application system in areas such as building curtain walls, industrial equipment, and transportation vehicles due to its technical characteristics and application value.

RAL 9007 is defined as "light gray" in the color chart system. Its color values have been authoritatively calibrated—L* brightness value 82.5, a* value -0.3, b* value 1.2, and a color difference ΔE ≤ 0.8 compared to the standard color chart, fully complying with the EU RAL-K7 color standard. This precise color performance stems from our three-coat, one-baking coating process: the substrate is selected from 1100, 3003, and 5052 series aluminum sheets, which undergo degreasing and chromating passivation pretreatment, followed by sequential spraying of zinc powder primer (film thickness 5-8μm), polyester topcoat (film thickness 20-25μm), and finally high-temperature curing at 230℃ to form a complete coating system, ensuring color uniformity and adhesion stability.

From a technical performance perspective, the core advantage of ral 9007 grey aluminum sheet lies in the balance between mechanical properties and weather resistance. Taking a commonly used 1.2mm thick RAL 9007 3003 coated aluminum sheet as an example, its tensile strength can reach 145MPa, yield strength 95MPa, and elongation ≥12%. While meeting the requirements of secondary processing such as bending and stamping, it avoids coating cracking during the forming process. In terms of weather resistance, after 4000 hours of QUV accelerated aging testing, the coating gloss retention rate still reaches over 85%, the color difference ΔE ≤1.5, and there is no red rust after 720 hours of salt spray testing, making it fully suitable for harsh environments such as high humidity in coastal areas and industrial pollution.

Key performance parameters of ral 9007 grey aluminum sheet:

Weather resistance: In the Q-UV accelerated aging test (ASTM G154), the fluorocarbon coated aluminum sheet retains ≥85% of its gloss after 3000 hours of irradiation, with 100% film integrity.

Corrosion resistance: No red rust is observed after 2000 hours of neutral salt spray testing (ASTM B117), conforming to ISO 9227 NSS standards.

Mechanical properties: Pencil hardness ≥3H (ASTM D3363), no cracks are observed in the bending test (ASTM D5279) with a radius of 1T (sheet thickness).

Fire resistance: Meets the GB 8624-2012 flammability rating, achieving A2 grade non-combustible material standards.

The flexibility in substrate selection is another major feature of our products. For different applications, we offer corresponding RAL 9007 grey aluminum sheets in various alloy series: the 1100 series is suitable for signage and signage applications requiring high-frequency bending, with its pure aluminum composition providing excellent formability; the 3003 series contains manganese, offering superior corrosion resistance and strength, and is often used for food equipment housings; the 5052 series, with its magnesium-enhanced mechanical properties, is an ideal choice for outdoor curtain walls and transportation equipment. All substrates comply with standards, with impurity content controlled below 0.15%, ensuring coating adhesion meets standards—a cross-cut adhesion grade of 0 and a circle-cut adhesion grade of ≥4B.

In production control, we utilize online coating thickness gauges and color spectrophotometers. Each batch of products undergoes three random sampling tests to ensure coating film thickness deviation is controlled within ±2μm. For customized needs, we offer sheet materials ranging from 0.3-6.0mm in thickness and up to 1220mm in width. We also support deep processing services such as shearing, lamination, and slitting, with a processing accuracy of ±0.1mm.

Currently, this RAL 9007 gray aluminum sheet is widely used in building curtain walls, industrial equipment, subway car interiors, high and low voltage switchgear enclosures, and commercial air conditioning panels. Its stable performance has earned long-term cooperation and recognition from companies such as Schneider Electric, Gree Electric, and BYD. We promise that every batch of products comes with a material certificate and test report, providing a 10-year coating quality guarantee, offering reliable assurance for our customers' production cycles. Whether it's confirming technical parameters or adapting to application scenarios, our engineering team provides one-on-one professional support to ensure precise matching between materials and end-user needs.