Fabrication method for making brazed heat exchanger with enhanced parting sheets

A method of constructing a heat exchanger comprising:

• providing a plurality of metal walls having a boiling side, a cooling side and at least one bonding surface;
• applying thermally conductive particles to a boiling side of a plurality of metal components;
• heating said plurality of metal walls with applied thermally conductive particles to a first temperature to integrally bond said thermally conductive particles together to form an enhanced boiling surface and allowing said plurality of metal walls with the enhanced boiling surface to cool,
• assembling said plurality of metal walls with the enhanced boiling surface with a spacing member so that said boiling sides of said plurality of metal walls with the enhanced boiling surface define a boiling passage and said cooling sides of said plurality of metal walls with the enhanced boiling surface define a cooling passage and providing layers of metal between said bonding surfaces of said plurality of metal walls with the enhanced boiling surface and adjacent surfaces of the spacing member;
• and
• heating the assembly in a vacuum furnace using a vacuum aluminum brazing process to a second temperature that is less than said first temperature, said second temperature being about 500° C., and maintaining said second temperature for an extended period of time to off-gas residual amounts of said thermally conductive particles and then heating the assembly to a third temperature that is about 100° C. greater than said second temperature and less than said first temperature to bond the layers of metal to at least one of the adjacent surfaces of the spacing member and the bonding surfaces of the plurality of metal walls with the enhanced boiling surface.