The influence of joining method of AW-7020 aluminium alloy on corrosion properties

The results of corrosion properties research of aluminum alloy AW 7020 (AlZn5Mg1) welded by friction stir welding FSW and MIG were presented. Friction Stir Welding (FSW) - a new technology can be successfully used for butt welding of different types of aluminum alloy sheets. In the article the parameters for friction stir welding of sheets made of AlZn5Mg1 [7020] alloy was presented as well as parameters for MIG. Metallographic analysis of bonds showed a proper structural construction of both, the FSW and MIG welded 7020 aluminum alloys. The polarization was carried out at changes in the potential speed of 12 mV/min in the range of š 50 mV with the stationary potential. Atlas 0531EU & IA potentiostat was used for studies. The corrosion resistance research was carried out using three electrode potentiodynamic method. The following parameters were measured: electrode potential Ec [mV] and the corrosion current density Jc [mi A/cm2]. The tests were carried out on specimens in 3.5% water solution NaCl. Good resistance to electrochemical corrosion was found of the native material, friction stir welded and MIG welded 7020 aluminum alloys. Original value are received results of the corrosion properties of new method friction stir welded AlZn5Mg1 alloy compared with traditional MIG method and the native material.