Will aluminum alloy doors and windows rust?

2025,11,05

Aluminum Alloy Doors and Windows: Corrosion Resistance and Building Applications

In the field of building doors and windows, aluminum alloys, with their unique physicochemical properties, have become a preferred material in modern architecture, balancing performance and aesthetics. Their core advantage stems from the material's inherent corrosion resistance mechanism, a characteristic that profoundly influences their application in construction and future development trends.

1. Material Characteristics: A Natural Protective Layer Built from an Oxide Film

The corrosion resistance of aluminum alloys originates from the dense alumina film formed on their surface. When the aluminum substrate is exposed to air, it rapidly reacts with oxygen to form an oxide film approximately 5-10 nanometers thick. This film has self-healing capabilities—even if partially damaged, the aluminum will continue to oxidize and form a new protective layer. This dynamic protective mechanism makes aluminum alloys virtually rust-free in normal environments, unlike the loose rust formed by oxidation in steel.

Experimental data shows that in salt spray tests simulating marine climates, untreated aluminum alloy specimens required continuous exposure for over 1000 hours before showing slight corrosion, while steel specimens under the same conditions developed noticeable rust spots in just 24 hours. This characteristic extends the service life of aluminum alloy doors and windows in coastal areas by 3-5 times compared to traditional steel doors and windows.

2. Advantages: The Art of Balancing Performance and Cost

Lightweight and High Strength Coexist

Aluminum alloy has only 1/3 the density of steel, but by adding alloying elements such as magnesium and silicon, its tensile strength can reach 200-350 MPa. Taking 6063-T5 profiles as an example, an aluminum alloy window frame with a wall thickness of 1.8mm can withstand a level 12 wind pressure (approximately 3.5 kPa), while a steel window frame of the same strength increases in weight by 40%. This characteristic allows aluminum alloy doors and windows to meet structural safety requirements in high-rise buildings without increasing the building load due to excessive weight.

Life-Cycle Economic Efficiency

Surface treatment processes (such as anodizing and powder coating) can further improve corrosion resistance. Aluminum alloy doors and windows with fluorocarbon coatings, in ultraviolet accelerated aging tests, show a color difference ΔE < 1.5 after 2000 hours, far exceeding the national standard requirement of ΔE < 3. Although the initial cost is 20%-30% higher than PVC Windows and doors, they require no replacement during their 30-year design life, reducing maintenance costs by over 60%.

Functional Integration and Innovation: Modern Aluminum Alloy Windows and doors utilize thermal break technology, dividing the profile into inner and outer parts connected by a polyamide strip. This reduces the heat transfer coefficient (U-value) from 6.5W/(m²·K) to 1.8W/(m²·K). Combined with triple-silver Low-E glass, overall energy efficiency is improved by 40%, meeting the three-star green building certification standard.

3. Building Adaptability: Scenario-Based Solutions

Climate Adaptability Design: In frigid regions, aluminum alloy windows and doors employ a multi-cavity structure design, coupled with silicone sealing strips, achieving an airtightness level of 8 (the highest level in national standards), effectively preventing cold air infiltration. In humid and hot regions, optimized drainage hole layout (3 drainage holes per meter of profile) combined with a concealed drainage system prevents rainwater backflow.

Spatial Aesthetic Expression: Breakthroughs in surface treatment processes allow aluminum alloy windows and doors to present diverse visual effects. Wood grain transfer technology can simulate the natural textures of oak and walnut wood, with a color difference ΔE < 0.8; electrophoretic coating can achieve metallic textures such as champagne gold and titanium gray, meeting the design needs of styles like Neo-Chinese and Modern Minimalist.

Intelligent Upgrades: Intelligent door and window systems integrating temperature and light sensors can automatically adjust the opening angle according to environmental changes. For example, when the indoor CO₂ concentration exceeds 1000ppm, the system automatically opens the fresh air window; during a rainstorm warning, the windows automatically close and lock. Although the unit price of these products is 40%-60% higher than traditional doors and windows, their penetration rate in the high-end residential market has reached 15%.

4. Development Trends: Technology-Driven Industrial Upgrading

Material Innovation: The application rate of recycled aluminum will increase from 30% in 2024 to 60% in 2025, reducing carbon emissions by 9 tons per ton of recycled aluminum production. Simultaneously, high-strength and high-toughness 7-series aluminum alloys (tensile strength > 500MPa) are beginning to be used in curtain wall systems for ultra-high-rise buildings, breaking through the strength limits of traditional 6063 profiles.

A Comprehensive Standards System

The new national standards implemented in 2025 require that the wall thickness of main window profiles increase from 1.4mm to 1.8mm, with repeated opening and closing performance categorized into 100,000 and 200,000 cycles, and a design life of no less than 30 years. These standards are driving industry concentration, and it is projected that the market share of leading companies will exceed 40% by 2030.

Systematic Solutions

The "whole-house window and door integration" model is emerging, with companies providing comprehensive solutions ranging from system windows and smart sunrooms to fireproof entrance doors. For example, a photovoltaic integrated window and door system can generate up to 200kWh of electricity per window annually, meeting basic household electricity needs.

5. Special Environmental Response Strategies

Despite the strong corrosion resistance of aluminum alloys, targeted protection is still necessary in extreme environments:

Marine climate zones: Utilize AAMA 2605 standard fluorocarbon coatings; salt spray testing must pass 5000 hours of certification.

Chemical pollution zones: Increase surface passivation treatment of profiles; use EPDM sealing strips instead of ordinary PVC.

High humidity zones: Equip with automatic drainage valves; fill profile cavities with desiccant.

The corrosion resistance of aluminum alloy doors and windows is essentially a perfect combination of materials science and environmental engineering. From atomic-level oxide film protection to systematic design at the architectural scale, and then to green transformation at the industrial level, this material system is reshaping the performance boundaries of building envelopes through continuous innovation. With the in-depth implementation of the "dual-carbon" strategy, aluminum alloy doors and windows will play a greater role in energy conservation, intelligence, and sustainability, becoming an indispensable "green skin" for modern buildings.

Author:

Ms. Rebecca Lee

E-mail:

sale01@wddoorwins.com

Phone/WhatsApp:

+86 13502225784