Heat sink is a kind of heat dissipation device for electronic components in electrical appliances, made of aluminum alloy, brass or bronze plate, flake, flake, etc., heat sink stamping processing...

 

How is the heat sink/radiator produced by stamping

details

First we need to know what is the heat sink, heat sink is a kind of to electrical appliances used hot electron component cooling devices, much by aluminum alloy, brass or bronze plate, plate, sheet, etc., more CPU in a computer, such as central processor to use a considerable heat sink, power supply in TV tube, pipe, power amplifier, power amplifier tube should be used in the heat sink. In general, heat sinks should be coated with a layer of heat-conducting silicone grease in the contact surface between electronic components and heat sinks in use, so that the heat emitted by components can be more effectively transmitted to the heat sinks, and then distributed to the surrounding air through the heat sinks. In terms of heat sink material, the thermal conductivity of each material is different, which is arranged from high to low according to the thermal conductivity, namely silver, copper, aluminum and steel. But it would be too expensive to use silver as a radiator, so the best solution is copper. Although aluminium is much cheaper, its heat conduction is obviously not as good as copper's (which is only about 50% of copper's). At present, the commonly used heat sink material is copper and aluminum alloy, both of which have their advantages and disadvantages. Copper has good thermal conductivity, but the price is more expensive, the processing difficulty is higher, the weight is too big (many pure copper radiators have exceeded the CPU's weight limit), the heat capacity is small, and easy to oxidize. Pure aluminum is too soft, can not be used directly, are used to provide enough hardness of aluminum alloy, aluminum alloy is cheap, light weight, but the heat conductivity is much worse than copper. Some radiators take each point, in the aluminum alloy radiator base embedded in a piece of copper. For ordinary users, the use of aluminum heat sink has been enough to meet the heat demand. The radiator in the north for heating in winter is also called the radiator. Heat sink occupies important role in the composition of radiator, besides the active heat dissipation of fan, evaluate the stand or fall of a radiator, depend greatly on the heat absorption ability of heat sink itself and heat conduction ability.

The radiator

Fin the basic production process, product demand - drawing development - mold making - test (extrusion aluminum) - cutting, CNC machining - function size sample confirmation - colour (spray anodic oxidation or other) - packaging - production inputs (test) - delivery of the goods.

The radiator

1. Aluminum extrusion type radiator aluminous material qualitative because itself soft easy processing characteristics of application in the radiator market early, simple said is extruded aluminum technology will aluminum ingots after high temperature heating, the aluminum liquid under high pressure through the groove of the extrusion mould, make the heat sink in the early embryo, but again to heat sink in the early embryo cutting, cross cutting, such as processing and then made into our common to the heat sink. Extruded aluminum heat sink of low cost, technical threshold requirement is not high also, but due to the limitation of itself material thickness and the ratio of the length of the cooling fins cannot exceed 1:18, so within the limited space, it is difficult to increase the cooling area, so the extruded aluminum heat sink cooling effect is poorer, it is hard to do today's rising high frequency CPU.

The radiator

2. At present, the main materials used by the mainstream heat sinks in the market are no more than aluminum and copper, and the copper plug process is the product of combining the advantages of aluminum and copper. Copper plug technology is based on the principle of hot expansion and cold contraction, aluminum extrusion heat sink is heated and copper core is inserted into it, and then the whole cooling is carried out. Because no third party medium is used, copper plug process can greatly reduce the thermal resistance between contact surfaces, not only to ensure the compact degree of copper-aluminum bonding, but also to make full use of the characteristics of fast aluminum heat dissipation and copper heat absorption. This kind of copper plug technology cost moderate heat dissipation effect is also good, is the main type of heat dissipation fins on the market.

The radiator

3. Compaction is the stacking of numerous copper or aluminum sheets, which are pressurized on both sides and polished to a section that comes into contact with the CPU core while the other side is stretched out as a fin for a radiator. Pressure solid legal system for the radiator that its characteristic is can do a lot of number of fins, and does not require high technology can ensure every fins can keep good contact with the CPU core (or near), and also between the fins are closely contact, by means of pressure of solid heat conduction between the loss will be significantly reduced, it is because the pressure of solid legal radiator with fins, this kind of radiator cooling effect is often good, weight is more light than traditional radiator.

The radiator

4. Forging heat sink forging process is formed by heating aluminum blocks and filling the mold with high pressure. Its advantage is that the fin height can reach more than 50mm and the thickness is less than 1mm, the maximum heat dissipation area can be obtained in the same volume, and the forging can easily obtain good dimensional accuracy and surface finish. But when forging, due to the low plasticity of the metal, deformation is easy to produce cracking, deformation resistance is large, the need for large tons (more than 500 tons) of forging machinery, but also because of the high cost of equipment and mold, resulting in high product cost, even many overclocking enthusiasts are not happy to enjoy.

The radiator

5. Jointed radiator fin Because the traditional aluminum-extruded radiator fin cannot break the proportional limit of fin thickness and length, so the jointed radiator fin is adopted. The fins are made of aluminum or copper plates and then attached to a grooved base using a thermal paste or solder. The feature of the combined fin is that the fin breaks through the original proportion limit, the heat dissipation effect is good, but also can choose different materials for the fin. Of course, the disadvantages are also obvious, that is, the use of thermally conductive paste and solder joint to combine the fin and base will have the interface impedance problem, which will affect the heat dissipation, in order to improve these disadvantages, two new technologies have been applied in the heat dissipation field. First is slotting technology, it is the use of more than 60 tons of pressure, the aluminum in the base of copper, and without using any medium between aluminum and copper, from the point of view of microscopic aluminum and copper atoms are connected to a certain extent, and thus to completely avoid the traditional copper aluminum combination produces the deficiencies of the interface thermal resistance, greatly improves the ability of heat to products. The second is the reflow welding technology. The biggest problem of the traditional jointed fin is the interface impedance, and the reflow welding technology is an improvement of this problem. Actually, reflow soldering and the traditional process of mating type heat sink is almost the same, just use a special welding furnace, it can be accurate to set of welding temperature and time parameters, using lead tin solder alloys, make full contact of the welding and welding of metal, thereby avoiding the leakage welding empty welding, ensure the connection of fins and the base as closely as possible, minimize the interface thermal resistance, and can control each solder welding copper melting time and melt temperature, uniform, ensure that all welds but this special soldering furnace back is very expensive, motherboard manufacturer, with more and radiator manufacturer is rarely used.

The radiator

6. Compared with aluminum-extruded heat sinks, the cutting technology solves the limitation of the ratio of fin thickness to length of heat sinks. The cutting process is to use a special tool to cut the whole material into layers of fins. The fins can be as thin as 0.5mm, and the fins of the fins are integrated with the base, so there is no problem of interface impedance. However, this cutting technology in the production process of more waste and low volume rate of the impact of the high cost, so the cutting technology mainly tends to copper heat sink.