The test is under the premise of hot-dip galvanized steel and aluminized zinc steel with the same thickness, coating and surface treatment. Aluminized zinc has better corrosion resistance than hot-dip galvanized, and its service life is 2-6 times that of ordinary galvanized steel.
3.Light reflection performance
Aluminized zinc has twice the ability to reflect heat and light than galvanized steel, and its reflectivity is greater than 0.70, which is better than 0.65 specified by the EPA Energy Star.
4.Heat resistance
Ordinary hot-dip galvanized products usually do not exceed 230 degrees, and 250 degrees will change color, while aluminized zinc plate can be used for a long time under 315 degrees. In the 300-degree environment for 120 hours, Baosteel's heat-resistant passivated aluminum-zinc plated steel has a much lower color change than aluminum and aluminum-plated plates.
5.Mechanical properties
The mechanical properties of aluminized zinc steel sheet are mainly manifested in yield strength, tensile strength and elongation. Ordinary DC51D grade 150g / sq. Galvanized steel plate generally has a yield strength between 140-300mpa, a tensile strength between 200-330, and an elongation between 13-25. The grade of DC51D + AZ aluminized zinc-plated aluminized zinc steel plate with a yield of 150 g / square is between 230-400mpa, the tensile strength is between 230-550, and the extension rail is between 15-45.
Because aluminized zinc is a high-density coated alloy steel, in addition to the above advantages, there are some defects:
(1)Welding performance
Due to the increase of mechanical properties, the surface of the inner substrate has a better coating density and a relatively high manganese content. Therefore, the aluminum-zinc coating cannot be welded under ordinary welding conditions and can only be connected by other parties such as rivets. In terms of welding, hot-dip galvanized steel performs better without welding problems.
(2)Applicability of tide temperature concrete
The composition of the aluminized zinc coating contains aluminum, and the aluminum component is prone to chemical reactions in direct contact with acidic wet concrete. Therefore, it is not very suitable for floor boards.
(3)Coating thickness and steel plate thickness restrictions
Most of the domestic aluminized zinc production units are converted from hot galvanized units, and there are certain restrictions on the thickness of aluminized zinc steel plates. The thickness of the steel plate is limited to 0.27 to 2.5. In terms of coating, it can only achieve a minimum of 30 grams per square and a maximum of 220 grams per square.
