In building drainage systems, components such as eaves gutters and drainage ditches are subjected to harsh conditions including alternating wet and dry periods, water immersion, outdoor exposure to sunlight, and freeze-thaw cycles. Ordinary aluminum materials often suffer from problems such as seam cracking, rust perforation, high-temperature creep sagging, and paint powdering and peeling, directly leading to a chain of problems such as roof leaks and facade pollution. Compared to general-purpose 3003 aluminum coils, 3105-H24 aluminum coils, with their higher matrix strength, superior forming toughness, and long-term corrosion resistance, have become the preferred material for building drainage components such as gutters and downpipes. BCM Aluminum strictly adheres to the ASTM B209 standard in the mass production of 3105-H24 aluminum coils, precisely matching the processing and service requirements of gutters, providing long-life drainage system material solutions for building projects worldwide.
From an alloy and temper design perspective, 3105 belongs to the aluminum-manganese rust-resistant alloy family. Based on 3003, it optimizes the manganese and magnesium ratio, improving matrix strength and fatigue resistance while maintaining excellent corrosion resistance. It is a sub-grade specifically developed for building envelopes and drainage components. The H24 temper, through a process of cold rolling hardening followed by controlled low-temperature annealing, fully releases rolling stress while achieving semi-hard strength. Compared to the H14 temper of the same hardness level, its elongation is increased by approximately 30%, and the material springback is reduced by more than 20%. In terms of specific mechanical properties, 3105-H24 has a stable tensile strength of 145–185 MPa, a yield strength ≥120 MPa, and an elongation ≥10%. It possesses sufficient structural rigidity to prevent sagging due to long-term water accumulation, and also exhibits excellent cold bending forming performance, making it suitable for common gutter production processes such as 90-degree folding, edge rolling, and interlocking. After forming, the joints are tight and free of microscopic cracks, eliminating the risk of leakage at the processing level.
For the specific working conditions of drainage scenarios, the weather resistance and fatigue resistance of 3105-H24 aluminum coils are particularly outstanding. The 3105 alloy itself possesses excellent resistance to atmospheric corrosion and water immersion. The dense passivation film formed by manganese effectively resists the corrosion of rainwater, acid rain, and weak acids from fallen leaves and humus. It shows no significant corrosion after more than 800 hours of neutral salt spray testing, far superior to ordinary pure aluminum. Simultaneously, the low internal stress characteristics of the H24 state prevent stress cracking and cumulative deformation under the long-term effects of seasonal temperature fluctuations and freeze-thaw cycles, avoiding problems such as loosening of joints and weld detachment caused by thermal expansion and contraction. The material's service temperature range covers -40℃ to 80℃, showing no significant creep or softening under high summer temperatures and no brittleness or cracking under low winter temperatures, adapting to the outdoor building needs of different climate zones worldwide.
In terms of engineering adaptability and quality control, BCM 3105-H24 aluminum coil for gutter are perfectly suited to the characteristics of on-site production and construction. The product's standard thickness ranges from 0.3mm to 1.2mm, with 0.4mm, 0.6mm, and 0.8mm being the mainstream engineering specifications. Width can be customized according to the gutter cross-sectional dimensions, with cutting accuracy controlled within ±0.5mm; thickness tolerance is stable at ±0.02mm; and board flatness is ≤1.5mm/m, ensuring consistent dimensions and smooth seams during continuous roll forming, eliminating the need for additional alignment. Surface finishes offer three options: natural rolled finish, polyester pre-coated finish, and fluorocarbon pre-coated finish. The pre-coated version further enhances weather resistance and color retention; the color difference within the same batch for standard colors such as white and gray is ΔE≤1.0, balancing protective performance with aesthetic requirements for building facades. Each batch of products comes with complete mechanical performance and corrosion resistance test reports, supporting project acceptance and quality traceability worldwide.
Although gutters are small building components, they directly affect the overall service life of the roofing system. 3105-H24 aluminum coils offer a triple balance of strength, formability, and corrosion resistance, addressing common failure issues in drainage components at their source. BCM Aluminum will continue to provide global building clients with specialized aluminum materials for gutter systems suitable for various working conditions through precise process control and stable product quality, ensuring reliable long-term performance even in concealed projects.
