cladding ratio of 4004/3003/4004 cladding alu

Three-layer aluminum alloy cladding brazing sheet is an important material for manufacturing brazed heat exchangers, of which 4004/3003/4004 is the most widely used aluminum alloy composite brazing sheet. The 4004/3003/4004 aluminum alloy composite brazing sheet was hot-rolled and clad, the distribution of the cladding layer in the width direction and the thickness difference of the upper and lower cladding layers were analyzed, and the difference of the cladding ratio after rolling was studied under different initial cladding ratios. The change rule plays an important guiding role in the control of the thickness of the cladding layer of the brazing sheet in actual production.



aluminum alloy cladding brazing sheet is a high value-added layered metal composite material, which has the advantages of light weight, corrosion resistance, good electrical and thermal conductivity, and excellent brazing performance. It is widely used in automobiles, construction machinery, household appliances, Air separation equipment, various radiators, condensers, evaporators and other fields in air compressors. Aluminum alloy composite brazing sheet is mainly produced by hot rolling and compositing, that is, two or more aluminum alloy slabs are stacked together, and after high temperature heating, severe plastic deformation caused by large rolling deformation is adopted. effect and high temperature thermal effect, so that it produces metallurgical bonding, thereby obtaining a composite sheet. In the 4004/3003/4004 brazing sheet, the melting point of the cladding layer 4004 alloy is 550-583°C, and the melting point of the base 3003 alloy is 643-654°C. The melting point of the 4004 alloy is more than 60°C lower than that of the 3003 alloy. 4004/3003/4004 aluminum alloy cladding brazing sheet is a better aluminum alloy composite brazing sheet.
 
The cladding ratio of the aluminum alloy cladding brazing sheet refers to the percentage of the thickness of the single-sided brazing filler metal cladding layer to the total thickness. This is a very important performance indicator that directly affects the success of the brazing process. If the coating ratio is too small, the supply of brazing filler metal will be insufficient during brazing, resulting in false welding or false welding, affecting the heat transfer and firmness of the heat exchanger, and in severe cases, the product will be scrapped; The thickness of the core material is relatively small, and it is often difficult to support the weight of the heat exchanger and the pressure of the jig during brazing, resulting in collapse. Therefore, how much cladding can ensure sufficient solder supply without catastrophic collapse is an extremely important issue. In addition, the stability of the cladding rate of the composite brazing sheet is also an important criterion for measuring the quality of the composite sheet. The stability of the cladding rate directly affects the brazing performance and brazing quality of the brazing sheet. Domestic and foreign standards have made strict regulations on the thickness and cladding rate of the cladding layer.