Friction stir welding （FSW）technology is a solid-phase connection technology.

It can seal and connect water chambers with the outer cover, which are  formed by different processes .This method does not require solder or flux, and can ensure that the entire weld joint obtains a uniform and consistent welding depth and a dense weld structure in the forged state. It has good sealing performance, high weld strength, and is close to the base material.

ü FSW & Extrusion 

Suitable for using extrusion technology to directly shape the cold plate flow channel, and opening the cycle through machining. The liquid cooling plate components are assembled using friction welding technology for welding and sealing. The surface of this type of liquid cooling plate is not suitable for too many screw holes.

ü FSW C&  Die casting

Die casting followed by friction stir welding: The water chamber is formed using die casting technology, which controls issues such as impurities and pores in the process. Further use friction welding for connection, which needs to improve reliability to avoid water leakage issues.

ü Flow channel design: Design the cold plate flow channel structure based on manufacturing process, product conditions, thermal resistance distribution, and other factors, including the size of the cold plate, flow channel structure, and inlet and outlet positions.

ü The flow channel design needs to meet the following requirements for friction stir welding process:

Welding structure of cover plate: There are mainly three types of welding structures: overlap, butt overlap, and non planar. The butt overlap is a conventional water-cooled plate welding structure, which has the best welding effect. The overlap step of the cover plate is not less than 1mm to avoid collapse during the welding process.

Cover plate machining allowance: As the surface needs to be milled flat after welding, the thickness of the cover plate generally needs to have CNC machining allowance. The general cover plate thickness is 2-3mm, with an allowance of about 0.5mm, which can meet the pressure within 1 megapascal.

ü Weld edge margin: There should be a margin of friction stir welding stirring head at the edge of the weld. Generally, for a 3mm cover plate, at least 5mm margin should be left at the edge to avoid edge welding collapse. It is best to communicate with the welding process party before design.

ü High heat dissipation efficiency

The cooling effect is relatively good, the temperature equalization effect is good, and it can cool down more quickly, suitable for situations that require high cooling speed.

ü Meet more complex design needs

The flow channels can be arranged reasonably according to the position of the heat source, and the shape of the flow channels can be achieved through the shape of bent pipes. Accurate heat dissipation design avoids excessive temperature differences in the system.

ü Others

It also has characteristics such as corrosion resistance, high temperature resistance, and uniform heat dissipation.

Key points of profile Tube Cold Plate

ü Material of substrate: Try to avoid having two metals with significant electrode potential differences in a system to reduce electrochemical corrosion.

ü Structure of cold plate types: Based on the structure of the liquid cooling system and whether it bears weight.

ü Design  of flow rate: Due to the large size of the water-cooled system, simulation analysis of the entire system is generally not conducted. Instead, the flow rate of the water-cooled radiator is set first, and then the water pump is matched based on the corresponding system flow resistance. After determining the total heat and physical properties of the working fluid, the flow rate and temperature rise are inversely proportional.

ü Friction stir welding has a simple welding process, high production efficiency, and is suitable for mass production.

ü The welding process does not require additional welding materials, which is economical and environmentally friendly.

ü Walmate ready to provide professional and more economical opinions based on your specific application scenario and demand scale.