The process of "Roll-Bonding" is known for the production of heat exchangers in flat plate collectors or refrigerators. The advantage of the method is that you can optimally shape the cooling channels and the joining process is accompanied by the rolling process. The process of roll bonding is shown in Fig.

Two sheet metal coils are unrolled through an unwinder and then aligned by a suitable roller stand. Before the sheets are printed by screen printing process with a graphite pattern is still a precise cleaning of the sheets. The printed graphite powder pattern describes the geometry of the later channels. The use of graphite serves as a release agent, thus the two boards can not permanently connect in these areas. After screen printing, the coils are heated and then pressed together by high-pressure rollers. Here, the two starting sheets are rolled with a respective sheet thickness of about 1.5 mm to a total of 1.5 mm. Finally, there is a water cooling and cutting the sheets to the desired length instead.

Fig .: Process principle of Roll-Bonding (Source: Talum, Tovarna aluminija d.d.)