Galvalume Roofing Sheet is a flat carbon steel product coated on both sides with an aluminium-zinc alloy. The coating is composed of 55% aluminium, 43.4% zinc and 1.6% silicon and applied by means of a continuous hot dip galvanizing process. Galvalume Sheet is available in a wide range of steel grades: steels for cold forming and deep drawing applications, and structural steels.
The excellent corrosion resistance of Galvalume Sheet is a result of the properties of its two metallic constituents: the barrier effect of the aluminium present on the surface of the coating and the sacrificial protection of zinc.
The characteristic spangled silver colour of Galvalume Sheet gives it a very attractive appearance. Thanks to a thin transparent layer of aluminum oxide on the top surface of the coating, this appearance is preserved over time.
Specifications of Galvalume Roofing Sheet:
1) Chemical Composition: 55% Aluminum, 43.4% Zinc, 1.6% Silicon
2) Substrate: Galvalume steel sheet & Pre-painted galvalume steel sheet
3) Standard: JIS3321/ASTM A792M
4) Alu-zinc Coating: 40/㎡-275/㎡
5) Galvalume Steel Thickness: 0.15mm to 0.8mm, all available
6) Prepainted Galvalume Steel Thickness: 0.16mm - 0.8mm, all available
7) Aluminum Coating: AZ50/AZ100/AZ150/AZ185
8) Spangle: regular spangle, minimized spangle, zero spangle
9) Surface treatment: Chemical treatment, oil, dry, anti-finger print
10) Features: long-term resistance to atmospheric corrosion, bright surface, paintability, durability and versatility
Types of Galvalume Roofing Sheet:
SMC Standard Sheet Metal Gauge:
Forming and joining
The forming and joining techniques currently used for uncoated steel sheets are also suitable for Galvalume Roofing Sheet.
The coating thickness must therefore be compatible with both the desired degree of corrosion protection and the requirements of the forming and welding processes envisaged. Forming performance is improved if Galvalume Roofing Sheet is coated with an thin organic coating.
Galvalume Sheet can be painted after degreasing and surface treatment when delivered oiled. Galvalume Sheet coated with an thin organic coating can be painted directly, without any prior surface treatment. However, the paint must be compatible with the resin.
In electrical resistance welding, the welding current must be suitably regulated and regularly adjusted. Electrode life can be extended by regularly stepping up the welding current and periodically dressing (machining) the electrodes.
Packaging of Galvalume Roofing Sheet
Shanghai Metal Products are packed and labeled according to the regulations and customer's requests. Great care is taken to avoid any damage which might be caused during storage or transportation. In addition, clear labels are tagged on the outside of the packages for easy identification of the product I. D. and quality information.
1) Shanghai Metal Standard
Galvalume Roofing Sheet is supplied passivated or oiled to temporarily limit any risk of black rust formation. During transport and storage, all necessary precautions must be taken to keep the material dry and to prevent the formation of condensation.
Applications of Galvalume Sheet:
1) Galvalume Sheet coated steels are used widely in both indoor and outdoor
2) Construction: roofing, cladding, structural sections, composite panels, tiles, etc.
3) Appliances: washing machines, tumble dryers, refrigerators, toasters, microwave ovens, etc.
4) Miscellaneous: boiler casings, air ducts, electrical cabinets, lighting, computer casings, etc.
Features of Galvalume Roofing Sheet:
1) Good corrosion resistance at high temperatures
2) Good abrasion resistance because of its surface hardness
3) Excellent thermal and light reflectivity
4) Galvalume Roofing Sheet can be supplied oiled and/or with a chemical surface treatment, or with an thin organic coating