Abstract: A method is disclosed for brazing without filler metal two components, of which at least one is an Al alloy. According to the method, prior to brazing, at least one Al alloy component is maintained in a region of temperatures included between the temperature of solvus T.sub.v of the alloy and 2/5 of temperature of fusion (solidus) T.sub.s of the alloy, expressed in degrees Kelvin, for a sufficient period of time. After this treatment, which may or may not be isothermal, the alloy is suitable for brazing in a domain of temperatures included between the temperature of fusion T.sub.e of the most fusible eutectic corresponding to the equilibrium diagram of the constituents of the alloy, and that of the solidus of the alloy. The method permits the realization of perfectly homogeneous brazed seams for alloys considered not to be brazable.

Abstract: A weldable aluminum alloy workable into sheet form containing Si, Mg and Cu, and a process for its production are disclosed.The alloy comprises (in percent by weight) proportions of Si and Mg as defined by a trapezium having the following co-ordinates:______________________________________ Si Mg ______________________________________ (A) 0.5 0.1 (B) 0.5 0.2 (C) 1.3 0.5 (D) 1.3 0.1 ______________________________________Cu: 0.1-0.5;Mn: 0-0.2;Ti: 0-0.1;Fe: 0-0.35;other impurites each: .ltoreq.0.05total impurity content: .ltoreq.0.15balance Al.The production procedure comprises semi-continuous or continuous casting of blanks, an optional homogenisation operation, a hot transformation operation which is terminated in the range of 270.degree. to 340.degree. C., an optional cold transformation operation, a complete solution treatment, a shaping operation using stamping or pressing, folding, bending, etc . . . , and a tempering operation.