摘要 |
PURPOSE:To form a porous boiling heat transfer surface having a high performance on the surface of an aluminum material by superposing a molding manufactured by heating and brazing a powder mixture of aluminum and a brazing material in a molding flask in a specific atmosphere on the surface of the aluminum material and brazing these materials CONSTITUTION:A mixture composed of aluminum powder of about 20-1,000mum and brazing material powder consisting basically of aluminum is put into a non- solderable molding flask formed of stainless steel or the like and is brazed by heating to about 600 deg.C, thereby manufacturing a porous molding. The molding or the cut part of such molding is placed on an aluminum base material via an aluminum brazing sheet and is brazed by heating to form a porous layer at >=1mm.. The need for a post stage such as washing is eliminated by the above- mentioned method. |