The processing process of profile radiator

Many people are curious about the forming process of profile radiators, and they are curious about what kind of processing can make them look like this. It is very delicate, and today we will reveal the secret for you!

Aluminum die-casting technology

In addition to aluminum extrusion technology, another commonly used process method for manufacturing heat dissipation fins is aluminum die-casting. By melting aluminum ingots into a liquid state, filling them into a metal model, and using a die-casting machine to directly mold them, heat dissipation fins can be made into various three-dimensional shapes using the die-casting method. The heat dissipation fins can be made into complex shapes according to needs, and can also be combined with fans and airflow directions to create heat dissipation fins with guiding effects, And it can make thin and dense fins to increase the heat dissipation area, which is widely adopted due to its simple process. The commonly used die-casting aluminum alloy is ADC12. Due to its good formability, it is suitable for making thin castings. However, due to its poor thermal conductivity (about 96 W/m.K), AA1070 aluminum is now mostly used as die-casting material in China, with a thermal conductivity of up to around 200 W/m.K, which has good heat dissipation effect.

However, there are some inherent shortcomings that AA1070 aluminum alloy die-casting radiators cannot overcome on their own:

(1) Excessive surface flow patterns and oxidation slag during die casting can reduce the heat transfer effect.

(2) When cooling, the internal micro shrinkage pores are relatively high, and the actual thermal conductivity decreases (K<200 W/m.K).

(3) The mold is prone to erosion, resulting in a shorter lifespan.

(4) Poor formability, not suitable for thin castings.

(5) The material is soft and prone to deformation.

With the continuous increase of CPU frequency, in order to achieve better heat dissipation effect, the volume of aluminum heat sinks produced by die-casting technology continues to increase, which brings many problems to the installation of the heat sink. Moreover, the effective heat dissipation area of the heat sink produced by this process is limited. To achieve better heat dissipation effect, it is necessary to increase the fan air volume, which in turn generates greater noise.

Aluminum extrusion technology

Aluminum extrusion technology simply means heating the aluminum ingot at a high temperature of about 520-540 ℃, allowing the aluminum liquid to flow through the extrusion mold with grooves under high pressure to create the initial heat sink, and then cutting and grooving the initial heat sink to create the commonly used heat sink. Aluminum extrusion technology is relatively easy to implement and has relatively low equipment costs, which has also made it widely used in the low-end market in previous years. The commonly used aluminum extrusion material is AA6063, which has good thermal conductivity (about 160-180 W/m.K) and processability. However, due to the limitations of its own material, the ratio of thickness to length of the heat dissipation fins cannot exceed 1:18, making it difficult to increase the heat dissipation area in limited space. Therefore, the heat dissipation effect of aluminum extruded heat dissipation fins is relatively poor, making it difficult to cope with the increasing frequency of CPUs today.

Flexible process

The flexible manufacturing process involves folding copper or aluminum thin plates into integrated fins using a molding machine, fixing the upper and lower bottom plates with a piercing die, and then using a high-frequency metal fusion machine to weld them into a processed base. Due to the continuous connection of the manufacturing process, it is suitable for making high thickness to length ratio heat dissipation fins. Moreover, the fins are formed as a whole, which is conducive to the continuity of heat conduction. The thickness of the fins is only 0.1mm, which can greatly reduce the material demand, And obtain the maximum heat transfer area within the allowable weight of the heat sink. In order to achieve mass production and overcome the interface impedance during material bonding, the production process adopts simultaneous feeding of upper and lower bottom plates, and the automation process is consistent. The upper and lower bottom plate bonding adopts high cycle fusion welding, that is, material fusion to prevent the generation of interface impedance and establish high-strength, closely spaced heat dissipation fins. Due to the continuous manufacturing process, it can be produced in large quantities, and due to the significant reduction in weight and improved efficiency, it can increase heat transfer efficiency.

Forging process

The forging process is formed by heating the aluminum block to the lowering point and using high pressure to fill the mold. Its advantages are that the fin height can reach over 50mm and the thickness is less than 1mm, which can achieve the maximum heat dissipation area in the same volume. Moreover, forging is easy to achieve good dimensional accuracy and surface finish. However, during forging, due to the phenomenon of necking during cooling plastic flow, the heat dissipation fins are prone to uneven thickness and height, which affects the heat dissipation efficiency. Due to the low plasticity of the metal, it is easy to crack during deformation, and the deformation resistance is high, requiring large tonnage (over 500 tons) forging machinery. It is also due to the high cost of equipment and molds that the product cost is extremely high. And due to the high cost of equipment and molds, the cost is too high unless produced in large quantities.

There are currently not many manufacturers in the world capable of producing cold forged heat sinks, the most famous being Japan's ALPHA, while Taiwan is Taisol, MALICO Taiye Technology. The advantage of cold forging is that it can produce heat dissipation fins with a larger heat dissipation area than aluminum extrusion. Due to the stretching process of aluminum extrusion, the aluminum metal structure is expanded horizontally, while the cold satin direction is vertically compressed. Therefore, cold forging has a significant advantage in heat dissipation, but its disadvantage is high cost and there are not many manufacturers with technology to manufacture and produce.

The entire production process of the profile radiator is very delicate, with every step being taken