The invention relates to a method for making or manufacturing plate stacks, particularly for manufacturing or producing coolers, cooler elements or heat sinks. The coolers, cooler elements or heat sinks are made up of at least one plate stack, with at least two plate-shaped elements made of metal, for example copper. They are provided with passages or openings and wherein the stacked elements are bonded with each other using a bonding means on joining surfaces formed by surface sides of said elements by means of heating to a process temperature to form the stack.
Coolers, also known as micro-coolers, are known in the art for cooling electrical components or modules, particularly high-power components or modules. The coolers consist of thin metal (metal foil) plates joined with each other to form a stack, the inner plates being structured, i.e. provided with openings or passages, so as to form cooling channels or flow paths for a coolant in the interior of the plate stack or cooler. For surface joining of the plates, they are provided with a joining means on their joining surfaces, i.e. on their surface sides. In order to join or connect the plates, the latter are stacked one on top of the other in a stack and then heated to a suitable process temperature, in which a fusible metal area (joining or hot-melt layer) is produced on the joining surfaces using the joining means, so that after cooling of the stacks they are joined with each other to form the plate stack.
The disadvantage of the known method is that contractions, or unwanted hollow or dead spaces, are formed in the interior of this stack at the junction between openings or passages of two adjoining plates during solidification of the joining or hot-melt layer, which (dead spaces) cause unwanted turbulence in the coolant flowing through the cooler formed by the plate stack.