The cumulative global production of zinc aluminized steel has reached 24 million tons since it entered the practical stage in 1972, and the annual production is about 3 million tons.
About 30-35% of the aluminum-zinc coated steel sheets are color-tinted and used for roofs and walls of buildings.
The surface of zinc-coated steel sheet has a characteristic smooth, flat and gorgeous starburst, and the base color is silvery white. The special plating structure gives it excellent corrosion resistance. It has a normal service life of 25a and is heat resistant and can be used in high temperature environments up to 315°C. It has good adhesion between the plating and the paint film and has good processing properties for stamping, shearing, welding, etc. The surface conductivity is very good.
The coating composition is composed of 55% aluminum, 43.4% zinc and 1.6% silicon by weight. The production process of Al-Zn coated steel is similar to that of galvanized steel and aluminized steel, which is a continuous melt coating process. 55% Al-Zn alloy coated Al-Zn steel has superior corrosion resistance compared to galvanized steel of the same thickness when both sides are exposed to the same environment. 55% Al-Zn alloy coated Al-Zn steel not only has good corrosion resistance, but also has excellent adhesion and flexibility of color coated products.
Since the steel sheet is subject to oxidation and rust when exposed to moisture, the surface must be protected with an anti-corrosion layer, which is generally divided into hot-dip galvanized Zn and hot-dip aluminum-zinc alloy Al-Zn (the composition of the aluminum-zinc alloy is 55% aluminum, 43.5% zinc and 1.5% silicon, referred to as 55% Al-Zn). According to the data, 55% Al-Zn is 4 times more anticorrosive than the same thickness of galvanization.
1. Heat reflectivity.
The heat reflectivity of zinc aluminized steel is twice as high as that of galvanized steel, which is often used as a thermal insulation material.
2. Heat resistance.
Aluzinc steel has good heat resistance and can withstand temperatures of over 300 degrees Celsius, similar to the high-temperature oxidation resistance of aluminized steel, and is often used in chimney pipes, ovens, luminaries and fluorescent light covers. Corrosion resistance.
The corrosion resistance of aluminized zinc steel coils is mainly due to the aluminum, which is protective. When the zinc is subjected to wear, the aluminum forms a dense layer of aluminum oxide, preventing further corrosion of the interior by corrosion-resistant materials.
Because the density of 55% AL-Zn is less than that of Zn, the area of zinc aluminized steel is more than 3% larger than that of galvanized steel with the same weight and thickness of the plating.
4. Easy to paint
Excellent adhesion between zinc aluminized sheet and paint, no pre-treatment and weathering treatment is needed for painting.
The coating adhesion of the gold-plated layer of Alu-Zn steel sheet is excellent, so it can be directly coated on advertising and general use panels without pre-treatment such as Weathering.
5. Galvanized steel has a gorgeous silver-white surface.
6. Zinc aluminized steel sheet has similar processing and coating properties to galvanized steel sheet.
Construction: Roofs, walls, garages, soundproof walls, ducts and modular houses, etc.
Automobile: muffler, exhaust pipe, wiper attachment, fuel tank, truck box, etc.
Home appliance: refrigerator backsheet, gas stove, air conditioner, electronic microwave oven, LCD bezel, CRT explosion-proof belt, LED backlight, electrical cabinet, etc. Agriculture: pig house, chicken house, grain bin, greenhouse with pipes, etc.
Others: heat break insulation cover, heat exchanger, dryer, water warmer, etc.
Difference between galvanized sheet and aluminized galvanized sheet.
The difference between galvanized sheet and aluminized zinc sheet mainly lies in the difference of the coating. The surface of galvanized sheet is evenly distributed with a layer of zinc material, which plays the role of anodic protection for the parent material, that is to say, the alternative corrosion of zinc material protects the use of the parent material, and only when all the zinc is corroded can the parent material inside be harmed.
The surface coating of the aluminized zinc sheet is composed of 55% aluminum, 43.5% zinc and a small amount of other elements, and the surface of the aluminized zinc coating is microscopically a honeycomb structure, with zinc contained in the "honeycomb" made of aluminum. On the one hand, the anodic protection is greatly reduced because the zinc material is not easily electrolyzed by aluminum. Therefore, once the aluminized zinc plate is cut, it will rust quickly when the cut edge is basically unprotected, so the aluminized zinc plate should be cut as little as possible and the edge should be protected by rust-proof paint or zinc-rich paint once it is cut.
|alloy a380||a356 alloy|
|Heat resistant||heat treatment|
|alloy in astronee||induction heating|
|vs zinc alloy||zinc alloy coated steel|