Forging process technology
The forging process is to heat the aluminium block to the depression point after heating and fill the die with high pressure. Its advantage is that the fin height can reach more than 50 mm and the thickness is less than 1 mm. It can get the maximum heat dissipation area in the same volume, and forging is easy to get good dimensional accuracy and surface finish. But when forging, because of the necking phenomenon of cooling plastic rheology, heat sinks are prone to uneven thickness and height, thus affecting the heat dissipation efficiency. Because of the low plasticity of metal, cracking is prone to occur during deformation and large deformation resistance, large tonnage forging machinery (more than 500 tons) is needed. It is also because of the high cost of equipment and dies that the product costs are extremely high. And because of the high cost of equipment and die, unless mass production, the cost is too high.
Planer and Cutting Technology
Sao Paulo radiator planer process is to make long strip embryos with grooves by extrusion, and then use special tools to cut out the first embryo layer by layer of fins. The thickness of fins can be thinner than 0.5mm, and the fins and the bottom plate are formed in one body, so as to avoid the trouble of multi-material combination of interface impedance. The disadvantage is that in the process of forming, due to the concentration of material stress, the joint of fin and bottom plate will produce cracks that are not easily perceived by naked eyes, which will affect the radiator's heat dissipation performance, and because of waste, production capacity and defective rate, the production cost is higher. Cutting technology is a one-time cutting of a whole piece of metal, forming very thin, very dense heat dissipation fins, thus effectively increasing the heat dissipation area. Because the hardness of metal can not be too high for cutting, the content of aluminium is slightly higher than that of ordinary aluminium alloy radiator. The quality of the radiator after forming is very light and easy to install. Although the raw material cost of this technology is comparable to that of conventional die-casting radiator, it requires high technology and is difficult to process, so there are not many products.
Precision Cutting Technology
Precision cutting technology is to cut a whole profile (aluminium/copper) with a special cutting machine tool on the base to cut the heat dissipating fins with specified spacing. Compared with traditional aluminum extrusion process, precision cutting technology can cut larger heat dissipation area per unit volume (increase by more than 50%). The surface of heat sink cut by precision cutting technology will form coarse particles, which can make the contact surface between heat sink and air larger and improve the heat dissipation efficiency. The biggest advantage of precision cutting is that the radiator belongs to integral cutting and forming, and the fin and base are combined as a whole. The heat sink manufactured by precision cutting technology does not have the problem of interface thermal resistance, and the heat conduction efficiency is very high.