CHARACTERIZATION OF JOINTS WELDED BY THE TIG PROCESS OF WELDING OF 7075 T6 ALUMINIUM ALLOYS

Our work consisted to study the influence of heat treatments on the hardness of the alloy of aluminum 7075 T6 and to distinguish a better characteristic of the evolution of the structure during the welding process TIG in the heated affected zone. We noticed that the evolutions of the supersaturated solid solution during the ageing treatments are in accordance with the sequences of the classic precipitation. An increase or a continuation at an isothermal maintaining leads to an appearance of equilibrium phases that are incoherent with the matrix. The experience has showed the evolution of the precipitate state through the welding process.