What Are Galvalume Steel Sheets?
Galvalume steel sheets are metallic steel sheets plated with aluminum, zinc, and silicon. They are also called aluminum-zinc alloy-plated steel sheets.
Galvalume building materials are rust-resistant and have a long durability period despite being a metallic material.
Another advantage is that it is robust and earthquake resistant. It has high solar heat reflectance and can suppress surface and indoor temperatures, especially in summer.
Uses of Galvalume Steel Sheets
Galvalume is widely used as a building material due to its excellent durability, heat resistance, and workability. It is also often used as an exterior material for houses because of its high design quality. Because of its high corrosion resistance, it is mainly used for exterior walls and roofs of buildings.
Galvalume is also used in a wide range of other applications, including machinery and equipment.
The following are examples of where Galvalume steel sheets are used:
- Pipes for agriculture and marine transportation
- Highway soundproofing walls
- Various industrial facilities and industrial equipment exposed to corrosive environments
- Electrical equipment such as microwave ovens and vending machines
- Automobiles
- Shipbuilding
Galvalume steel sheets have a wide range of applications as shown above due to their excellent properties.
Characteristics of Galvalume Steel Sheet
Galvalume steel sheet is a rolled steel sheet plated with galvalume. Plating is mainly done by melting, since it is an alloy. The composition of galvalume is 55% aluminum, 43.4% zinc, and 1.6% silicon.
Aluminum is characterized by long-term durability and heat resistance. Zinc also produces galvanic action. Galvanic action is the oxidation of zinc, which forms an oxide film and has a rust-preventive effect. It is also called a sacrificial corrosion prevention effect.
Galvalume steel sheet is a steel material that has the durability and heat resistance of aluminum and the corrosion resistance of zinc, as described above.
Types of Galvalume Steel Sheets
Galvalume is a steel material with the characteristics described above. It is widely used in applications ranging from construction materials to machinery and equipment.
Super galvalume steel sheet, also called SGL steel sheet, is a next-generation steel sheet. It is a steel material developed to further improve the durability of galvalume steel sheets, and is manufactured by adding about 2% magnesium to the plating. The magnesium makes the plating structure even denser and provides high corrosion resistance.
Other Information on Galvalume Steel Sheets
1. How to Use Galvalume Steel Sheets
Galvalume steel sheets are installed and laid in the same manner as tin roofs and steel pipes. However, galvalume steel sheets have maintenance requirements, one of which is flushing. By focusing on flushing areas that are not easily exposed to rainwater, the rust-preventing effect can be enhanced.
In addition, in mountainous areas where roads are prone to freezing, sodium chloride and calcium chloride are sometimes sprayed to prevent freezing. If these substances adhere to the roof, rusting may easily progress. Therefore, it is necessary to thoroughly wash the roof with water after spraying anti-freezing agents.
2. History of Galvalume Steel Sheets
Prior to the development of galvalume steel sheet, tin and other materials were used as exterior materials. Galvanized tin is a steel material plated with hot-dip zinc. The galvanic action of the zinc makes the material corrosion resistant, and it was widely used around the world.
In the 1960s, acid rain caused by pollution from industrialization became a social problem. Even corrosion-resistant tin corrodes when rain with a low PH level falls, resulting in a problem of low durability. Against the backdrop of this problem, galvalume steel was introduced.
Galvalume steel was developed by the American steel company Bethlehem Steel in 1972. It is more than three times more durable than tin, depending on installation conditions and other factors. As a result, it has become widely used throughout the world as an alternative to tin.
3. Life Span of Galvalume Steel
Galvalume is known to have a longer service life than tin. The life span of exterior materials made of tin is about 10 to 20 years. In contrast, galvalume has a life expectancy of 25 to 35 years.
The actual lifespan varies depending on the manufacturer and the environment in which it is used, and in some cases it can be used for 50 years or more.
In recent years, a steel material called super galvalume steel (SGL steel) has also become popular; SGL steel is a more durable version of galvalume steel and can be expected to last 30 to 50 years.