Optimisation of t-joint properties in Al-Mg-Si alloy laser welding

Abstract

One of the main aims in aircraft production today is to develop materials and methods of construction that are more economically durable. One possibility is to improve the mechanical properties of aluminium alloys. To this end, new techniques have been developed, such as the optimisation of T-joint properties in the laser welding of Al-Mg-Si alloys. This, however, brings into play many operating factors, whose interrelation needs to be understood for the selection of parameters for welding. To study this, the factorial design approach is an appropriate solution. T-joint welding was carried out using two cw laser heads. With the optimum parameters, a good tensile strength was achieved. Simultaneous or sequential welding leads to different weld depths, but with similar values for tensile strength within the optimum parameter range. A cross-section of the weld shows a V-shaped seam, which gives the highest tensile strength for the different laser configurations. From the results of the factorial design, a second degree polynomial model can be created, to estimate, in the experimental field, the average tensile strength per mm of weld as a function of welding speed and wire volume deposited per mm of weld.One of the main aims in aircraft production today is to develop materials and methods of construction that are more economically durable. One possibility is to improve the mechanical properties of aluminium alloys. To this end, new techniques have been developed, such as the optimisation of T-joint properties in the laser welding of Al-Mg-Si alloys. This, however, brings into play many operating factors, whose interrelation needs to be understood for the selection of parameters for welding. To study this, the factorial design approach is an appropriate solution. T-joint welding was carried out using two cw laser heads. With the optimum parameters, a good tensile strength was achieved. Simultaneous or sequential welding leads to different weld depths, but with similar values for tensile strength within the optimum parameter range. A cross-section of the weld shows a V-shaped seam, which gives the highest tensile strength for the different laser configurations. From the results of the factorial design, a se...