Cooling device, method for producing a cooling device and power circuit
View Patent ↗A cooling device includes an aluminum heat sink and at least one nickel sheet segment. The nickel sheet segment is connected to the aluminum heat sink by a solder layer. The cooling device includes a securing surface for securing and for heat absorption. The securing surface being formed by that side of the nickel sheet segment which faces away from aluminum heat sink. The aluminum heat sink is formed from a plurality of aluminum sheets which are stacked one above another and are connected to one another. At least one aluminum sheet includes cutouts which form a cooling channel covered by at least one of the aluminum sheets. Furthermore, a method for producing a cooling device and also a power circuit comprising a heat sink as described here are presented.
1. A method for producing a cooling device, the method comprising:
stacking aluminum sheets to form an aluminum heat sink, at least one of the aluminum sheets having cutouts for forming a cooling channel;
connecting the stacked aluminum sheets to one another to form the aluminum heat sink; and
arranging a solder mediation layer on at least one of the aluminum sheets, which forms an outer side of the aluminum heat sink, either by direct cohesive application on at least one of the aluminum sheets before or after the steps of stacking and connecting, or by soldering, wherein a soldering compound is situated between the solder mediation layer and the aluminum sheet, wherein the soldering compound situated between the solder mediation layer and the aluminum sheet is melted by the heating in order to form a solder layer between the solder mediation layer and the aluminum heat sink.
2. The method of claim 1 , wherein connecting the stacked aluminum sheets comprises: fitting a screw connection extending through all the aluminum sheets, or a clip engaging around edges of all the aluminum sheets, or wherein connecting the stacked aluminum sheets comprises:
applying a soldering compound on a connecting surface of at least one aluminum sheet before the step of stacking; and
melting the soldering compound in order to form at least one solder layer between the aluminum sheets by heating the aluminum sheets together with the soldering compound, as a result of which the aluminum heat sink is produced as a stacked aluminum sheet structure, wherein the solder mediation layer is arranged by soldering, wherein soldering compound is situated between the solder mediation layer and the aluminum sheet, and the soldering compound situated between the solder mediation layer and the aluminum sheet is melted in the step of melting the soldering compound between the aluminum sheets in order to form a solder layer between the solder mediation layer and the aluminum heat sink.
3. The method of claim 1 , wherein before stacking at least one of the aluminum sheets is stamped in order to form a cooling channel as a result of the stacking by the surrounding aluminum sheets.
4. The method of claim 1 , wherein the he aluminum sheets are rolled aluminum sheets which are solderable by hard solder.
5. The method of claim 1 , wherein the solder mediation layer is formed as a nickel layer and has a proportion by mass of nickel of at least 70% or 85% nickel.
6. The method of claim 1 , wherein the solder mediation layer is formed as a nickel layer and has a proportion by mass of nickel of at least 95%, 98% or99% nickel.
7. The method of claim 1 , wherein the solder mediation layer has a thickness of not more than 150, 100 or 50 μm.