The radiator is the weaker link in auto parts. The auto parts radiator should have sufficient heat dissipation capacity and a long service life in a limited space. The entire assembly must be light in weight, consume less non-ferrous materials, and have low production costs. The technological development trends are as follows:
(1) Thin wall, light weight, and high efficiency radiator is a kind of vulnerable auto parts with high output value. The cost of materials is greater than the cost of heavy labor. How to further reduce material consumption is an urgent issue that needs to be solved worldwide. Generally, the cost of radiator raw materials accounts for 75% to 85% of the entire cost. Equipment maintenance costs only account for 3% to 7% of the total cost, and the wages of employees account for about 2% to 4% of the total cost. Therefore, reducing material consumption and improving production technology as well as structure can make auto parts radiators achieve thin wall, light weight and high efficiency.
(2) The structure is reasonable. In order to ensure sufficient heat dissipation capacity and reliability in the limited space, only by looking for improvement measures, reducing stress and improving heat transfer in the structure of auto parts radiators, can the design requirements be met. First of all, the uniform distribution of residual stress is ensured in the structure to avoid excessive local stress during stamping deformation, which leads to the uneven distribution of material source after stamping and the strength of the whole assembly is reduced. The welding area should be enlarged to reduce the stress. For example, the narrow groove structure of double side welding should be adopted for the main plate and water chamber, and the production technology and welding process should be fully considered when designing the structure. The wall thickness should be reduced as much as possible, and the method of increasing the wall thickness is not allowed to improve the assembly strength. For example, the wall thickness of main plate and water chamber should be controlled in the range of 0.6mm ~ 0.8mm, the material thickness of cooling water pipe should be within the range of 0.11mm ~ 0.13mm, and the thickness of heat sink should be 0.043mm ~ 0.06mm. If the thickness of the copper radiator exceeds the above value, the cost will increase, but the strength will not increase much.
(3) The use of low-tin solder and organic flux to manufacture copper radiators, and the use of high-efficiency nitrogen (N2) protective brazing processes to organize the production of aluminum radiators are the future development trends. The use of brazed aluminum radiators for cars and some light vehicles is a recent development trend. Substituting aluminum for copper can further reduce the weight of the radiator. In particular, the aluminum radiator produced by brazing can achieve the same strength of the entire assembly, thereby greatly improve the reliability of the radiator.