Alloyed hot-dip galvanized steel sheets (GA sheets) have excellent performance in terms of press formability, corrosion resistance, coating properties, and weldability, and are suitable for the development of lightweight and safe automobiles, and thus increasingly cause the automotive industry. Attention.
Alloyed hot-dip galvanized steel sheets were developed by the United States in the early 1960s. After its development has experienced a period of low valley, in recent years, with the increase of anti-corrosion requirements, it has attracted people's attention. This is because to meet the anti-corrosion requirements of the automobile body, the quality of the plating layer must be controlled to be more than 40 g/m2, and the production cost of the electrogalvanized sheet increases sharply with the increase of the thickness of the plating layer. Therefore, how to ensure the corrosion resistance of the steel surface under the condition of not increasing the production cost becomes an important issue. The research work shows that if the steel sheet is placed in the alloying annealing furnace immediately after hot-dip galvanizing of the continuous galvanizing line for alloying annealing, an iron-zinc alloy layer containing 10% of iron can be obtained. The electrode potential of the iron-zinc alloy layer is still lower than that of the substrate, but higher than that of the pure zinc layer, so that the erosion rate of the coating is lowered, the life is increased, and the corrosion resistance is improved. In addition, the weldability of alloyed galvanized steel sheets is also superior to that of general galvanized steel sheets.
At present, the technical points of interest in the development of GA steel sheets are:
1. Since the composition of the Zn-Fe alloy in the coating has a great influence on the final surface quality, it is the key technology of the alloyed hot-dip galvanized steel sheet to master and control the composition of the Zn-Fe alloy in the coating. After the surface layer of the steel sheet is alloyed, the alloy layer on the surface tends to be hard and brittle, and powdery peeling, that is, powdering, often occurs during processing. To this end, studies have shown that adding an appropriate amount of aluminum (0.10% or more) to the zinc solution, the iron content in the coating is controlled between 7% and 12%, which is beneficial to eliminate the hard and brittle phase in the coating and improve the coating. Anti-dusting ability.
2. Use multi-layer GA steel plate or film composite coated steel plate. In order to improve the characteristics of cationic electrocoating and press formability, the former is further coated with a two-layer GA steel plate rich in Fe layer. In order to ensure deep penetration, the substrate is mostly made of IF steel. The latter tries to form a Mg-containing phosphate film on the coating of 30 g/m2, which is superior to the general film organic composite plating plate in corrosion resistance and perforation. Since the late 1990s, the newly developed inorganic lubricating film GA steel sheet having a Mn-P composite oxide film has been put into practical use because of its low cost and similar performance.
3. Develop high-strength GA steel plates. In order to adapt to the weight of the car body, the application of high-strength steel plate is expanding, but the GA steel plate, which is the mainstream of the car body anti-rust plate, is restricted by the steel plate composition, that is, Si, Mn, etc. added due to the need of high strength are easily oxidized. The element is firstly oxidized externally in the heat treatment process of the continuous hot-dip galvanizing line, thereby affecting the compactness of zinc. At the same time, oxides such as SiO2 and Mn2SiO4 are formed on the surface of the steel sheet, causing problems of plating. For this reason, GA high-strength steel sheets suitable for various applications such as bake-hardening type (BH), precipitation-enhanced type, and structure-controlled type (DP, TRIP) have been developed and put into practical use.
Galv Cross Arm Cable Support Bracket
Product Name:Galv cross arm cable support bracket
Key words:Galv cross arm cable angle support bracket,Power cross arm cable support bracket,Cross arm cable support bracket for galv
Used to support angle for conner construction
Size:174x12x8
Part No.: Q.Q.Q.000020
Material elongation:20#
Finished: Galvanized,HDG,Plain,Painting,Dacromet,Electrogalvanizing,Oiled,Phosphorization,etc
Place of origina:China
HS Code:730820
Trademark:ZBRF
Color:Customized
Part:Power,Galv
Transport Package:Plastic Bag or Gunny bag and Wooden Case
Port of shipment:Shanghai Port,Taicang Port
Certification:CE,SGS,A.S
Galv Cross Arm Cable Support Bracket,Power Cross Arm Cable Support Bracket,Galv Cross Arm Cable Angle Bracket,Power Crossarm Cable Support
TAICANG ZHONGBO RAILWAY FASTENING CO., LTD. , https://www.railfastener.com