METHOD FOR ATTACHING METAL POWDER TO A HEAT TRANSFER SURFACE AND THE HEAT TRANSFER SURFACE

摘要

The purpose of the method developed is to form on top of a heat transfer surface a porous layer, which is to be fixed strongly to the surface below it at a temperature and time applicable for industrial production. The heat transfer surface is copper or copper alloy, preferably oxygen-free or deoxidised high phosphorous copper. The powder forming a porous surface is fine-grained copper powder or copper alloy powder. In the method according to the invention, a brazing solder containing preferably nickel, tin and phosphorous alloyed with copper, is brought to the heat transfer surface. The invention also relates to the heat transfer surface onto which a porous surface is formed by means of a powder of copper or copper alloy and the brazing solder described.