DEVELOPING EMPIRICAL RELATIONSHIPS TO PREDICT TENSILE, IMPACT AND FATIGUE STRENGTH OF GTA WELDED AA 6061 ALUMINIUM ALLOY INCORPORATING PULSED CURRENT PARAMETERS
Keywords:
Pulsed Current, Tungsten Inert Gas Welding, Aluminum Alloy, Tensile Strength, Impact Toughness, Fatigue Life, Design of Experiments, Analysis of VarianceAbstract
The preferred welding process for welding AA6061 aluminium alloy is frequently Gas Tungsten Arc (GTA) welding due to its comparatively easier applicability and better economy. In the case of single pass GTA welding of thinner section of this alloy, the pulsed current has been found beneficial due to its advantages over the conventional continuous current process. In this investigation an attempt has been made to develop empirical relationships to predict tensile strength, impact toughness and fatigue life of GTA welded AA6061 aluminium alloy joints by incorporating pulsed current parameters. One of the design of experiment concepts, full factorial design, has been used to design the number of experimental conditions. Regression analysis has been used to develop the empirical relationships. Analysis of variance technique has been used to identify the significant factors. Co-efficient of determination has been calculated to check the adequacy of the developed models. The developed relationships can be effectively used to predict mechanical properties of the GTA welded AA6061 aluminium alloy joints from pulsed current parameters.
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