Friction Stir Welded Water heat sinks for e-mobility
A water heat sink for e-mobility is an electronic device, which is made of aluminium casted parts and used for automotive applications (electronic housing). Aluminium casted heat sinks are mainly welded by Friction Stir Welding.
Why use FSW for casted aluminium heat sinks ?
Aluminium casted heat sinks welded by Friction Stir Welding present many advantages. The first one is a lower production cost than the previous technology (sealing and screwing). Their mechanical properties are higher: the use of high strength aluminium alloys ensures a higher resistance. They are also lighter, perfeclty waterproof and show excellent thermal conductivity (metallurgical junction).
Lower production cost
The price difference between sealing & screwing method and Stirweld solution is 33 %
Higher mechanical property
The use of high strength aluminium alloys ensures a higher resistance
No porosity, high quality watertight FSW seal
Excellent thermal conductivity
Already used in automotive industry
Where FSW is used in automobile industry?
Friction Stir Welding is used in different parts of automotive application. There are 3 types of components :
- Water cooling plate : this part is in aluminium casting and allows the cooling of the batteries of electric vehicles thanks to a cooling channel encloses thanks to a cover welded by FSW.
- Drive motor housing : it is an aluminium casting part – the water channel is situated around the motor to cool down an electrical motor. The housing is made by casting, and the cover of the water channel is welded by Friction Stir Welding technology.
- Electric control system : this part is composed with an aluminium box, made by casting. The electronic card is inside this housung, and it has to be cooled down.T hat is the reason why the box is made with aluminium, as the thermal conductivity is very high. We will perform the water channel inside this housing to cool down the box. And the cover of the water channel is welded by Friction Stir Welding.
FSW Welding of the active heat sink
An active heat sink is an aluminium component in which a fluid circulates in order to cool electronic components. It is an indispensable element of e-mobility.
Carrying out the welding of this part through FSW offers many advantages:
Heat sink parts before FSW.
– Cost reduced by 2
– Cycle time divided by 5
– Complete automatization
– Casting and FSW in the same place
– Action performed in one operation rather than 2 (sealing and screwing)
– 100% leak proof
– Higher repeatability
Internal part of a water heat sink for E-mobility.
Outside part of a water heat sink for E-mobility. Final part after FSW.
Water heat sink cost
Water heat sink market is emerging. The solution of assembling the hood to the heat sink by sealing & screwing is no longer relevant. New technologies have emerged, like friction stir welding, which has revolutionised aluminium welding.
See our price difference* between classical sealing & screwing method and FSW Stirweld solution
*cost per part for 70 000 parts/year
In comparing sealing & screwing method and the Stirweld solution with the FSW head, which adapts to your existing machine, two main factors play a role on the price: Cost of consumables & Quality cost.
Cost of consumables:
Sealing/screwing: € 2 per part
Stirweld solution: € 0.24 per part.
Time consuming quality control for sealing/screwing,
Higher defect rates with sealing/screwing.
The screwing & sealing solution is 4 times more expensive than the Stirweld solution.
As OEM batches are usually 2 to 3 times smaller than what was announced for the first five years, so it is better to invest in modular equipment in order to optimize your machine time and costs.
Moreover, the Stirweld solution offers you the same technical quality, at lower cost and with the possibility to modulate its machine park. Characteristics that a special machine does not have.
FSW is the key to reduce heat sink cost and to improve the quality and reliability.
If you whish to learn more about water heat sinks FSW Stirweld solution, you can attend our free webinar.