Heat Sink Fin Skiving Technology,heat sink fin skiving machines,heat sink with skived fins,heatsink making machine,heatsinks machine,heat sink skived machine,heat sink technologies

HEAT SINK FIN SKIVING TECHNOLOGY

The Skived fin, also known as skiving technology, simply takes an entire piece of aluminum or copper and use special skived machine to cut out fins with standard spacing and a certain thickness and height. Because of using high precision cutting technology, the integration of the forming, relative to other processing technology, the same volume of raw materials can be cut out more heat dissipation area, the heat transfer performance is more stable, in the same condition,the cooling performance is more than 1.5~2 times of the efficiency of traditional bonded fin or soldering heat sink, thus greatly improve heat dissipation efficiency and extend the service life of heating components.
Skived heat sinks can be constructed of aluminium or copper allowing for full, one-single-piece solutions without thermal barriers for high performance cooling.

Skived Fin Heat Sinks offerhighly optimized cooling as they allow for higher fin densities than what is manufacturable using extrusion methodologies, but do not have an interface joint that restricts heat flow like bonded or brazed fin heat sinks. Unlike bonded or brazed heat sinks, Skived Fin Heat Sinks are constructed from a single piece of material and offer reduced thermal resistance since there is no joint between a base and fins. These heat sinks are manufactured by precisely slicing the top of the base, called skiving, folding it back to where it is perpendicular to the base, and repeating at regular intervals to create fins.

The skiving process enables high fin density and thin fin heat sink geometries for optimal thermal performance. By packing as much fin surface area into a given volume, skived fin heat sinks have greater heat transfer than other single piece construction heat sinks such as extruded aluminum heat sinks. Compared to extruded aluminum, skived fin heat sink fabrication does not rely on expensive tooling, providing greater design flexibility and faster prototyping. Instead, each fin is cut separately using the same tool which allows for lower tooling costs.

SKIVED FIN HEAT SINK HAS THE FOLLOWING ADVANTAGES

(1) Perfect conductivity between base and fins. Because skived fin heat sink is a whole profile without any connection point, which can give full play to the heat dissipation characteristics of the heat sink.

(2) High fin densitie, Lori's skived fin process can make the skived fin more thinner and denser, with higher heat transfer efficiency.

(3) Great forced airflow solution, the skived fin processing technology is simpler than other liquid cooled heat sink, with lighter weight and lower cost.

(4) Compared with aluminum extrusion and other processes, skived heatsink is less limited in size and can be made wider, which can be used for heat transfer of machines with large power.

(5) Customized skived fin heat sink does not need expensive tooling which provides greater design flexibility. Instead, each skived fin is cut separately using the same tool which allows for lower tooling costs.

(6) Add a thermal interface material to the skvied fin heatsinks to better connect with your heat source and complete your thermal solution.

HOW TO IDENTIFY A SKIVED FIN HEAT SINK?

It is fairly easy to identify a Skived Heat sink as the heat sink has a curve where the blade finishes its cut at the base of the heatsink as shown in the picture. In addition, the fins are not completely vertical, and curve slightly. This is more pronounced at the fins get taller.

Typical width of the plate fin is 20~~500 mm, but it is possible to manufacture up to 600 mm wide heatsinks. As a Skived heatsink is manufactured from a long block of material, the only is no real limit to length of the heatsink is the length of the block. Different heights can be achieved by machining the block of material. Any excess material is recycled to reduce wastage. Typical Finishes for Aluminum skived heatsink are Anodization, or Nickel Plated. Typical finished for Copper Skived heatsinks are Anti-Oxidant, or Nickel Plated.

FABRICATION FOR HIGH FIN DENSITY HEAT SINKS PRODUCTION OF FIN SKIVED HEAT SINKS

How to identify a Skived Fin Heat sink?

It is fairly easy to identify a skived heat sink machine as the heat sink has a curve where the blade finishes its cut at the base of the heatsink as shown in the picture. In addition, the fins are not completely vertical, and curve slightly. This is more pronounced at the fins get taller.

Typical width of the plate fin is 20~~500 mm, but it is possible to manufacture up to 600 mm wide heatsinks. As a Skived heatsink is manufactured from a long block of material, the only is no real limit to length of the heatsink is the length of the block. Different heights can be achieved by machining the block of material. Any excess material is recycled to reduce wastage. Typical Finishes for Aluminum skived heatsink are Anodization, or Nickel Plated. Typical finished for Copper Skived heatsinks are Anti-Oxidant, or Nickel Plated.

Heat Sink Production by fin skiving - Production of skived heat sink
The Skived fin process produces heat sinks with 8~15% increasing of the cooling capacity as compared to the stitched fin process, 12~22% better thermal conductivity over extruded heat sinks and 62~74% over die-cast heat sinks.

Leading the heat dissipation with innovation high density ,high performance, high aspect ratio, excellent performance. Skived heat sinks are produced using a sharp knive that, as it passes over the material, curl up a small thickness of metal which is then bent vertically to form the fin. Skived fins are produced from a bar of material and then cut to length as required by the final application. The final heat sink can be machined using normal fabrication techniques. Because of the thin fins, care must be taken in handling to prevent damage. It is suggested that a shroud be placed over the fins to help prevent damage.

Fin Configuration
Thermal conductivity is only one piece of the puzzle to designing a good heat sink fins skiving machines. Squeezing out performance gains on heat sinks in the cutting edge chips and microprocessors found in smartphones, tablet and PCs, power applications, etc require innovation in the geometry and layout of the fins.
The key concept to grasp here is fin efficiency: the ratio of the fin heat transfer rate to the heat transfer rate of an ideal fin (one where Tfin = Tbase). The better the fin efficiency, the better the heat transfer via convection to the surrounding atmosphere. Optimizing the geometry of the fins helps maximize airflow through the heat sink.

Fin Efficiency
A heat sink fin receives heat from an electronic device and dissipates it into the surrounding coolant fluid. The heat transferred by a fin to the coolant medium decreases as the distance from the base of the heat sink increases. Using a material that has a higher thermal conductivity and decreasing the aspect ratio of the fins or/and using more fins help to boost the fins’ overall efficiency.

Schematic of idealized paane-strain skiving showing chip formation by smooth

laminar flow, with simple shearing/skiving tool.

The deformation zone (blue), undeformed chip thickess h0 and rake angle α are shown.The workpiece material undergoes plastic shape transformation to form a chip with final thickness hc. The velocity of bulk material flow against the tool is V0. The force in the direction of V0 is the cutting force.

Depending the rake angle, the tool wedge angle, the material and the speed of skiving,the proportion between thickness ho and thickness hc can be between 1 and 3 on average in fin skiving.

Example: If ho/hc = 2,5 and the skiving thickness ho is 0,9mm, then the fin thickness will be 2,25mm,This means also that you have to skive 250mm to get a fin of 100mm.

Laminar flow induced by change of deformation geometry (α=<45°)
Smooth streak lines show that the laminar flow is stable during the skiving operation and the flow mode forms a straight fin with constant thickness.

120 mm high fins skived for high power railway applications
High Power cooling heat sink production

Fin Forming during Skiving operation

During the skiving (cutting) of metal, the temperature of the interaction area of the skiving tool and workpiece becomes high. The temperature affects not only the rate of wear of the skiving tool but also the integrity of workpiece surface such as residual stress, hardness, and surface roughness. Fin skiving machines the cutting temperature is one of the very important factors of the mechanism of skiving process.

The Fin thickness h' will always be thicker than the skived layer h