| 摘要 |
PURPOSE:To obtain a brazed member excellent in surface treatment properties and corrosion resistance in post treatment by putting a member of Al or Al alloy in a vacuum state and then heating and brazing it as far as the brazing temperature in such an atmosphere that chloride or fluoride flux vapor exists. CONSTITUTION:When an assembly of Al or Al alloy member is put in such an atmosphere that chloride or fluoride flux vapor exists, the vapor attaches uniformly to the assembly and breaks oxide film on the surface and consequently wettability of the brazing filler metal is promoted. Further, this vapor combines with water and oxygen in the atmosphere and makes the atmosphere more non-oxidizing to prevent the surface of the member from being oxidized. Furthermore, the reason why the member is put in the vacuum state and then in the atmosphere wherein flux vapor exists is to supply ample flux into the inside of a member difficult for the flux vapor to circulate. |
