Aluminum-Plastic Co-extrusion Structure
Aluminum-plastic co-extruded doors and windows represent a new type of highly efficient composite profile, utilizing a composite and modular energy-saving design philosophy. They employ aluminum alloy profiles as a base material, upon which a layer of micro-foamed polyvinyl chloride (PVC) is applied to the outer surface using a micro-foaming extrusion molding process; the two materials are bonded together through high-temperature extrusion and encapsulation.
Characteristics of Aluminum-Plastic Co-extrusion
Doors and windows fabricated from this profile not only possess the strength and precision inherent in aluminum alloy windows but also combine the thermal insulation properties—as well as the tactile warmth—typically associated with plastic and wood windows. Furthermore, through surface transfer printing or lamination techniques, they can achieve the aesthetic and decorative effects of traditional wooden windows. Moreover, these composite windows exhibit excellent sound insulation performance, thereby meeting the rigorous performance requirements of high-grade green buildings and passive ultra-low-energy buildings. Additionally, because the underlying aluminum alloy profile is fully encapsulated by the PVC layer, its corrosion resistance is significantly enhanced.
Through a co-extrusion process, aluminum alloy and modified PVC (such as PE or PP) are fused into a single entity, forming a tightly bonded structure comprising an “aluminum alloy load-bearing layer” and a “polymeric anti-oxidation and thermal insulation layer.” These two materials are bonded at the molecular level, eliminating any risk of delamination.
Comparison of Core Advantages: Aluminum Alloy vs. Aluminum-Plastic Co-extrusion
- Superior Thermal Insulation Performance
Polymeric materials possess an extremely low thermal conductivity (approximately 0.03–0.1 W/(m·K))—significantly lower than that of aluminum alloys. The composite structure effectively eliminates thermal bridges, reducing the overall heat transfer coefficient (K-value) by 30%–50% compared to traditional aluminum alloy profiles. This makes it particularly well-suited for regions with cold or extreme-temperature climates, where it can significantly lower energy consumption for building air conditioning. - Balanced Lightweight Design and High Strength
The density of polymeric materials is merely one-fifth to one-third that of aluminum alloys. While the composite structure maintains robust resistance to wind pressure and deformation (thanks to the outer aluminum alloy layer and internal support framework), it simultaneously achieves a 20%–40% reduction in overall weight. This reduces the load-bearing burden on the curtain wall substructure, thereby lowering installation costs and minimizing structural stress on the building’s foundation. - Enhanced Corrosion Resistance and Durability
The inner layer of polymeric material exhibits excellent resistance to acids, alkalis, and aging, effectively shielding the aluminum alloy layer from corrosive elements such as moisture and salinity (a critical advantage in coastal or industrial environments). Meanwhile, the outer aluminum alloy layer—having undergone specialized surface treatments (e.g., fluorocarbon coating)—demonstrates weather resistance comparable to that of traditional profiles, resulting in a significantly extended overall service life.
