What exactly is a finned heat sink?

The most commonly used heat sinks for LED lighting fixtures are finned heat sinks. Why is that? Firstly, they are cost-effective, and secondly, they are easy to process. Let's take a closer look at what finned heat sinks are. The materials for finned heat sinks include good quality aluminum, iron, and copper, with copper being rare due to its high cost, which manufacturers generally avoid. There are two main manufacturing techniques: forging and extrusion. The following examples illustrate these processes: Finned heat sink forging process: The forging process of finned heat sinks involves heating aluminum blocks and filling them into molds under high pressure. The advantages include a fin height of over 50mm and a thickness of less than 1mm, allowing for a large heat dissipation area within the same volume. Forging can achieve good dimensional accuracy and surface roughness. However, due to the low plasticity of metals during forging, they can easily crack under deformation, and the high deformation resistance requires large tonnage (over 500 tons) hydraulic presses, which significantly increases equipment and mold costs, thereby raising product costs. Finned heat sinks are also involved in cutting, riveting, embedding, reflow soldering, and the popular high tower heat pipe radiator market. The mainstream radiator fins are typically standard square shapes, but some products have unique shapes. For instance, circular radiators represented by South Korean Simin and tower-type radiators represented by Tt have simpler riveting technology compared to other manufacturing techniques. This is also a common type in the low-end radiator market. The emerging mainstream market features tube-type radiators that use highly conductive heat pipes; the base of the radiator is made entirely of copper, while some manufacturers use all-copper designs for the fins while others opt for all-aluminum designs. The principle behind this design is that the all-copper base absorbs heat from the CPU and then quickly transfers it to the fins via the heat pipes for dissipation. From a theoretical standpoint, radiators using heat pipe technology require multiple transfers of heat before it can be dissipated. Therefore, the thermal resistance between different materials directly affects the overall performance of the radiator. Finned heat sink extrusion process: Aluminum is soft and easy to process, making it a long-standing material in the radiator market. In simple terms, aluminum extrusion technology involves heating aluminum ingots at high temperatures and then pouring molten aluminum into a grooved extrusion mold under high pressure to create fin blanks. These blanks are then cut and formed into the familiar fins we see. Aluminum extruded fins are cost-effective with a low technical threshold. However, due to material limitations, the ratio of thickness to length for fins cannot exceed 1:18. This makes it difficult to increase the heat dissipation area within limited space, thus reducing the cooling effect of aluminum extruded fins. It is evident that there are structural differences between these two types of radiators; stamping is relatively simple while die-casting can create complex shapes. However, one should not solely judge the quality of a radiator based on these factors; we should choose products that offer good value for money rather than just opting for high-end materials.

The most commonly used heat sinks for LED lighting fixtures arefin heat sinks, why is that? First, the cost is low, and second, it is easy to process. Let's learn together what fin heat sinks really are.

The materials for fin heat sinks include good aluminum, iron, and copper, with copper being rare due to its high cost, which manufacturers do not allow. There are two technologies: forging and extrusion. The following examples show:

Forging process of fin heat sinks:

The forging process of fin heat sinks involves heating aluminum blocks and filling them into molds under high pressure. The advantages are that the height of the fins is above 50mm, with a thickness of less than 1mm, allowing for a large heat dissipation area with the same volume. Forging easily achieves good dimensional accuracy and surface roughness. However, during forging, due to the low plasticity of metals, it is prone to cracking during deformation, and the deformation resistance is high, requiring large tonnage (over 500 tons) hydraulic presses. The high cost of equipment and molds also significantly increases product costs.

Fin heat sinks are used in cutting, riveting, embedding, reflow soldering, and the popular high tower heat pipe radiator market. The mainstream radiator fins are standard square in shape, but some products have their own shapes. Among them are round radiators represented by South Korea's Simin and tower-type radiators represented by Tt. Compared to other manufacturing technologies, riveting technology is relatively simple, which is also a common type in the low-end radiator market. The emerging mainstream market features tube-type radiators that use heat pipes with strong thermal conductivity. The bottom of the radiator uses all-copper materials, while some manufacturers use all-copper designs for the fins and others use all-aluminum designs. The principle behind this design is that the all-copper heat-absorbing bottom guides the CPU's heat and then quickly conducts it to the fins through the heat pipes for dissipation. From a theoretical perspective, radiators using heat pipe technology require several stages of conduction before dissipating heat. Therefore, the thermal resistance between different materials directly affects the overall performance of the radiator.

Extrusion process of fin heat sinks:

Aluminum is soft and easy to process, having been used in the radiator market for a long time. In simple terms, aluminum extrusion technology involves heating aluminum ingots at high temperatures and then pouring molten aluminum into a grooved extrusion mold under high pressure to create fin blanks. These blanks are then cut and formed into grooves to create the common fins we see. Aluminum extruded fins have low costs and low technical barriers. However, due to material limitations, the ratio of thickness to length of the fins cannot exceed 1:18. It is difficult to increase the heat dissipation area within limited space; therefore, the cooling effect of aluminum extruded fins is reduced.

It can be seen that there are differences in the structures of the two types of radiators; stamping is relatively simple while die-casting can create complex shapes. Of course, we cannot judge the quality of radiators solely based on this. We should choose items with a high cost-performance ratio rather than just opting for high-quality items.