Heatsinks
Bonded Fin Heatsink
WHAT IS A bonded fin heatsink?
Cofan’s Bonded-Fin heatsinks provide an efficient thermal management solution for high-power electronic components and systems. Engineered to handle significant thermal loads, they ensure the reliability and performance of various devices, including consumer electronics, industrial machinery, medical devices, telecommunications equipment, and military hardware. These heatsinks offer precise thermal management to maintain optimal operating temperatures and extend component lifespan. Custom-designed to meet specific thermal requirements, Cofan’s heatsinks effectively address different power levels and device sizes. They can also be integrated with advanced thermal management technologies, such as vapor chambers, heat pipes, and liquid cooling heat exchangers, to further enhance cooling efficiency, making them an optimal choice for superior thermal performance in diverse scenarios.
Technology Description
Cofan’s Bonded-Fin heatsinks efficiently dissipate heat from high-power electronic components and systems. They are versatile, suitable for consumer electronics, industrial, and military applications, and can handle both small and large-scale thermal challenges. These heatsinks can be integrated with vapor chambers, heat pipes, and liquid cooling heat exchangers for enhanced effectiveness. Constructed by joining heat-radiating fins to a heat-conducting base plate using methods like epoxy, soldering, crimping, or brazing, they ensure precise thermal management.
The method of manufacturing a bonded-fin heatsink allows for several advantages:
- Improved Thermal Performance: Bonded fin heatsinks can have thinner and more densely packed fins compared to extruded heatsinks, resulting in a larger surface area for heat dissipation. Additionally, Fin Aspect ratios over 50:1 can be achieved for maximum surface area availability.
- Design Flexibility: Manufacturers can create custom shapes and sizes to fit specific applications, accommodating various thermal and spatial requirements.
- Material Options (Custom Shapes and Sizes): Bonded fin heatsinks can be tailored to specific dimensions and shapes to fit unique spatial constraints and thermal requirements. This is especially useful in applications with limited or irregular spaces. Different materials can be used interchangeably for the base and fins such as electrical grade aluminum for its lightweight and thermal conductivity properties, or copper for its superior heat transfer and spreading properties. The ability to use different materials and customize the fin arrangement can lead to more efficient use of materials, potentially reducing costs
. - Variable heatsink Fin Density and Thickness: The spacing or fin density and orientation of fins can be designed or tailored to maximize airflow and minimize pressure drop resistance, improving the efficiency of both natural and forced convection cooling regimes. The heatsink fin thickness is another variable that can be controlled to optimize thermal performance.
- Selective heatsink Fin Location: This feature allows for the non-contiguous location of the heatsink fins to be placed in specific areas on the heatsink base. This allows for clearance areas to be created without having to use subtractive machining processes for fin removal to create hardware access zones and clearance areas.
- Custom / Enhanced Airflow Paths: The heatsink fin shape and location, or custom airflow deflectors can be designed to direct airflow in specific pathways to enhance cooling efficiency for particular applications.
- Large Heatsink Format: Bonded Fin heatsinks can be manufactured up to 60” x 40” (1500mm X 1000mm) in size.
- Enhanced Thermal Management Options: Bonded fin heatsinks can be easily integrated with fans or blowers to create hybrid cooling solutions, further enhancing thermal management capabilities. They can be further combined with heat pipes or vapor chambers to distribute heat more effectively across the heatsink.
- Quick Turn Prototyping: Bonded Fin heatsinks can be prototyped with without hard tooling investment.
Bonded Fin Heatsink Method of Manufacturing Process
Bonded fin heatsinks are manufactured using a process that involves attaching cooling fins to a heat-spreading base using thermal bonding techniques, such as soldering, brazing, or epoxy bonding. Bonded fin heatsink bases are typically manufactured in the following step.
1. Bonded Fin Heatsink Material Selection
- Base Material: Typically made from aluminum or copper depending on the thermal spreading requirement. Heat pipes and vapor chambers can be incorporated into the bonded fin base for enhanced thermal conductivity and overall performance improvement.
- Cooling Fin Material: Often, but not always, the same material as the base (aluminum or copper) to ensure good thermal conductivity and compatibility. CFD analysis is helpful in the selection of the material as it will help to determine the optimum cooling fin thickness, spacing, and efficiency.
2. Bonded Fin Heatsink Base Preparation
In manufacturing bonded fin heatsink bases, the base must first be created with multiple grooves where the cooling fins can be inserted and bonded, brazed, or soldered. There are two primary methods for creating these grooves:
1. Extrusion Process: In this process, the grooves are formed during the extrusion of the base (see Figure 1 below).
2. Machining Process: In this process, the grooves are machined into the base with a CNC machine (See Figure 2 below)
Figure 1
Figure 2
For prototyping or low-volume production, machining the grooves is usually more cost-effective. However, for high-volume production, extruding the grooves is more efficient but incurs some tooling costs.
Each method—machining or extruding the grooves—has its unique advantages. These are summarized in the capabilities chart below.
3. Cooling Fin Preparation
- Cutting and Forming: Fins are cut and formed from sheets of metal. They may be stamped, extruded, or machined to the required shape and size. This allows for enhanced dissipation features, such as flow-through ventilation, air flow turbulators or disrupters, and serrated fins for enhanced surface area.
4. Assembly and Bonding
- Placement: The cooling fins are placed into the grooves of the base (for grooved bases) or positioned on the flat base in the desired configuration with the assistance of a jig or fixture.
- Bonding Methods:
- Soldering: Fins and base are heated, and solder is applied to bond the fins to the base. This method provides a strong and thermally conductive bond. There are a variety of solders available from Indium to Sn/Pb depending on thermal performance requirements.
- Brazing: Similar to soldering, but performed at higher temperatures using a filler metal that melts and flows into the joint creating a metal-to-metal interface that results in the highest thermal conductivity between the base and the cooling fins.
- Epoxy Bonding: Thermally conductive epoxy adhesives are used to bond the fins to the base. This method is useful for complex shapes or materials that cannot withstand the high temperatures of soldering or brazing. It is generally the most cost-effective method of manufacturing a bonded fin heatsink.
Bonded-Fin Capabilities Chart
|
Feature
|
Inches
|
Metrics (mm)
|
Notes
|
||||||
|---|---|---|---|---|---|---|---|---|---|
|
Minimum
|
Maximum
|
Minimum
|
Maximum
|
||||||
|
Base Connstruction
|
Extruded
|
Machined
|
Extruded
|
Machined
|
Extruded
|
Machined
|
Extruded
|
Machined
|
|
|
Width
|
1.00
|
1.00
|
19.00
|
60.00
|
25.40
|
25.40
|
482.60
|
1524.00
|
Maximum machined width currently limited by existing equipment |
|
Flow Length
|
0.25
|
0.50
|
48.00
|
48.00
|
6.40
|
12.70
|
1219.20
|
1219.20
|
Flow lengths shown are practical limits. Above 48" additional design engineering required. |
|
Fin Height
|
0.02
|
0.02
|
6.00
|
6.00
|
0.50
|
0.50
|
152.40
|
152.40
|
Maximum height shown is practical limit. Taller heights are capable. After this height fin efficiency decreases. |
|
Fin Thickness
|
0.02
|
0.02
|
0.13
|
0.13
|
0.50
|
0.50
|
3.20
|
3.20
|
Machined bases can accommodate thicker fins, but shown is practical limit. |
|
Fin Spacing
|
0.05
|
0.05
|
1.00
|
1.00
|
1.30
|
1.30
|
25.40
|
25.40
|
There is no maximum limit on fin spacing. Shown is a practical limit. |
|
Base Thickness
|
0.15
|
0.15
|
1.50
|
3.00
|
3.80
|
3.80
|
38.10
|
76.20
|
Extruded maximum is limited by weight/foot property machined based thickness has no pracical limit. |
Crimped Fin Heatsink
WHAT IS A crimped fin heatsink?
Cofan’s crimped heatsink is a thermal management device designed to dissipate heat from electronic components. Made typically of aluminum, its structure includes a base and multiple fins. The fins are pressed into grooves or slots in the base through a crimping process, ensuring tight contact for efficient heat transfer. This cost-effective method makes crimped heatsinks popular. They are versatile and lightweight, suitable for various shapes, sizes, and applications, including consumer electronics, power electronics, LED lighting, and telecommunications. Their performance can be enhanced with thermal interface materials, fans, and heat pipes.
Extruded Heatsink
WHAT IS A Extruded heatsink?
An extruded heatsink is a type of thermal management device designed to dissipate heat from electronic components, ensuring they operate within safe temperature limits. The process of creating an extruded heatsink involves the extrusion of a metal, typically aluminum, through a die to form a continuous profile with fins or other features that enhance its ability to dissipate heat.
Extruded heatsinks are favored for their relatively low cost and high efficiency in thermal management. The extrusion process allows for the production of heatsinks in various shapes and sizes, tailored to specific applications and performance requirements. Additionally, the durability and lightweight properties of aluminum make these heatsinks suitable for a wide range of environments and conditions.
Skived Fin Heatsink
WHAT IS A skived fin heatsink?
The Benefits of a Skived Fin Heatsink
- High aspect ratio (Fin Density) >50:1 in both Copper and Aluminum without CNC machining. wire EDM or extruding
- Lower tooling costs
- No minimum material cost or production runs
- Preferred technology for replacing obsolete, out-of-stock or low-volume Al extrusion profiles with no material minimums
- Unitary fin-base construction (no welding, epoxy or brazing)
- May be integrated with heat pipes liquid cooling and fans for maximum thermal performance
- Eliminates voids, delamination and inhomogeneous
- High-density power cooling applications
- Economical Copper fabrication
- Quick sample turnaround times with optimum performance
What technology can skived fin heatsink replace?
Extruded Heatsinks
Preferred technology for replacing obsolete, out-of-stock, low-volume Al extrusion profiles with no material minimum or tooling. Skived fin can produce thermally equivalent and near net mechanical equivalency.
Bonded & Folded Fin Heatsinks
The skived fin process is able to create the same fin density as bonded and folded fin technology with improved thermal performance. The improved performance comes as the fins and base plate are integrated as a unitary structure and not bonded with epoxy or brazed creating the optimum thermal path.
Brazed Folded Fin Heat Exchanger Chassis
By integrating the skived fin heat exchanger (as a replacement for folded fins) into the base structure of the chassis, the brazing process can be eliminated. The skived Fin manufacturing process creates the low thermal impedance conduction path without a secondary operation.
|
Aluminum
|
Inches
|
Metric (MM)
|
||
|---|---|---|---|---|
|
|
Min
|
Max
|
Min
|
Max
|
|
*Flow Length
|
0.39
|
23.62
|
10
|
600
|
|
*Width
|
1.97
|
62.99
|
50
|
1600
|
|
Fin Height
|
0.20
|
4.72
|
5
|
120
|
|
Fin Thickness
|
0.004
|
0.08
|
0.1
|
2
|
|
Fin Gap
|
0.004
|
2.00
|
0.1
|
50
|
|
Base Thickness
|
0.02
|
1.38
|
0.5
|
35
|
|
Alloy
|
1060, 1100, 6063, 6101
|
|||
|
Copper
|
Inches
|
Metric (MM)
|
||
|---|---|---|---|---|
|
|
Min
|
Max
|
Min
|
Max
|
|
*Flow Length
|
0.39
|
11.811
|
10
|
300
|
|
*Width
|
1.97
|
62.992
|
50
|
1600
|
|
Fin Height
|
0.20
|
4.7244
|
5
|
120
|
|
Fin Thickness
|
0.004
|
0.0394
|
0.1
|
1
|
|
Fin Gap
|
0.004
|
1.378
|
0.1
|
35
|
|
Base Thickness
|
0.02
|
1.378
|
0.5
|
35
|
|
Alloy
|
C110
|
|||
Stacked Fin / Zipper Fin Heatsink
WHAT IS A stacked/zipper fin heatsink?
Cofan’s stacked fin heatsink dissipates heat from electronic components using multiple thin fins stacked on a base. Made from materials like aluminum or copper, the fins are attached through soldering, welding, or mechanical fastening. This design maximizes surface area for heat transfer while keeping a compact size, ideal for space-limited applications.
The manufacturing process includes fabricating and assembling individual fins onto the base, with techniques like soldering or thermal adhesives. Surface treatments like anodizing enhance performance and durability.
Cofan’s stacked fin heatsinks are efficient, compact, and versatile, suitable for computers, servers, telecommunications, power supplies, and LED lighting.
APPLICATIONS
Harness cables are used to organize and protect electrical wiring in applications such as automotive, aerospace, industrial machinery, and consumer electronics, ensuring efficient power distribution and signal transmission. They improve safety, reduce installation time, and enhance durability by bundling multiple wires into a single, structured assembly.