Pin Fin Heat Sinks
Optimum thermal management through Pin Fin heat sinks
Diehl Metall develops and produces powerful Pin Fin heat sinks, which provide an optimized thermal management in many applications. Due to their enlarged surface area with direct contact to the cooling medium, cold plates with pins offer excellent heat dissipation and are therefore used in high-performance electronics such as in the field of electric and hybrid vehicles, but also in LED technologies and applications for renewable energies.
We use copper and aluminum – both alloys with excellent conductive properties – to manufacture our pin fin plates. Due to the special arrangement of the pins, media streams can enter from all directions, thus enabling increased turbulence effects. Due to our extensive know-how we are able to easily adapt the heat sinks to individual customer requirements and thus to adapt them accordingly for a wide range of applications.
For our Pin Fin heat sinks we generally use materials with excellent thermal conductivity properties. Therefore, we offer copper, aluminium or a bimetallic compound of both alloys to be used as materials.
We determine which material is best to be used depending on the application-specific thermal requirements such as power, chip area and cooling area of the respective component. Depending on the requirements, certain parameters such as the coefficient of thermal expansion, high corrosion resistance and the potential for weight savings are also taken into account when selecting the appropriate material.
Copper as material for Pin Fin heat sinks offers excellent thermal conductivity (approx. 400 W/mK) due to its properties. The high thermal capacity of the material also ensures a pronounced ability to absorb power peaks. A thin metallic coating effectively protects the copper material from corrosion.
When it comes to hybrid modules of vehicles, copper is the high-end solution to choose as material for Pin Fin heat sinks, as no derating (power reduction) is caused by the inverter and thus the full power can be called up while driving.
In contrast to copper, aluminium gives a lower thermal conductivity – between 170 and 220 W/mK depending on the selected alloy. As a very light material, aluminium is particularly suitable when weight is to be saved in the application. Even without plating, the material itself offers an optimum corrosion protection against coolants, for example against the water-glycol mixture used in hybrid and electric motors.
Aluminium is therefore a cost-effective alternative as a material for Pin Fin heat sinks. Due to the lower performance of the material, it is necessary to check carefully whether the material is suitable for the respective requirements of the desired application.
Bimetall (Copper-Aluminium Compound)
To make the best possible use of the respective advantages of copper and aluminum, we also offer a hybrid solution for Pin Fin heatsinks made of both materials.
By combining copper and aluminum in a hybrid material, the weight of the component is lower and the corrosion protection against the coolant is given without plating. Furthermore, the heat spread is very good and peak loads can be absorbed for a short time.
We offer two methods of manufacturing pin fin heat sinks:
- Forging (hot forming)
- Impact extrusion (cold forming)
As an experienced development partner, we consider individual requirements and provide customer-specific solutions. Depending on the application, we advise our customers on the choice of material, shape (cylindrical or conical) and recommend the optimum manufacturing process for the respective special projects.
Forging is characterized by a particularly high degree of design freedom due to a thermally improved material flow. Based on decades of experience in this forming technology, we forge customer-specific Pin Fin heat sinks on fully automated equipment.
Advantages at a glance:
- High freedom of design for pin geometries
- Forming of secondary mould elements possible
- High volume output
- Geometry-related increased stiffness of the pins
- Improved heat dissipation from the base plate due to the (conical) shape
- Optimum heat dissipation in relation to the component weight
Impact extrusion is a particularly promising and sustainable process for the production of Pin Fin heat sinks, as raw materials and resources are used efficiently. Thus, this forming technology can contribute both to cost reduction on the customer side and to energy savings in the production process.
Advantages at a glance:
- High dimensional accuracy
- Better mechanical properties (e.g. tensile strength, hardness)
- Optimal material utilization
- High volume output
- Uniform distribution of the pressure loss in the fluid over the heat sink/pin height
Research & Development
In close cooperation with our customers we develop system-specific solutions in the field of thermal management. Based on customer requirements such as power output, installation space and overall rigidity, we develop the best possible Pin Fin solution. The entire development chain includes the iterative processing of the following steps:
- Component design
- Thermal system analysis (stationary and transient heat conduction)
- Structural mechanical component analysis (component strength and stiffness)
- Numerical simulations for the design and optimization of forming processes (forging or impact extrusion)
- Production of the tools and performance of preliminary tests
- Laboratory tests
Laboratory & Material Inspection
The range of services offered by our laboratory includes a wide variety of material tests on samples, semi-finished products and components. In addition, we carry out special investigations within the scope of development projects and advise and support our customers in all material questions. In doing so, we use recognised test methods:
- Hardness testing
- Microhardness testing
- Quantitative structural analysis
- Tensile test
- Chemical analysis
- Scanning electron microscope
- EDX microanalysis
- Technical cleanliness
- Plating analysis
- Design & Tool Manufacture
- Quality Management