Optimization of process parameters for friction stir welding of joining A6061 and A6082 alloys by Taguchi method

Abstract

The friction stir welding is a pioneering solid-state metal joining technique for producing high-quality joints in materials. In this article, Taguchi approach is applied to analyze the optimal process parameters for optimum tensile strength and hardness of welded dissimilar A6061 and A6082 alloys. An orthogonal array of L9 is implemented and the analysis of variance is employed to investigate the importance of parameters on responses. The experimental tests, conducted according to combination of rotational speed, tool tilt and types of tool pin profile parameters. The results indicate that the rotational speed is most significant process parameter that has the highest influence on tensile strength and hardness, followed by tool pin profile and tool tilt. The optimum results verified by conducting confirmation experiments. The predicted optimal value of tensile strength and hardness of dissimilar joints produced by friction stir welding are 267.74 MPa and 80.55 HRB, respectively.

Influence of secondary phase particles Al2O3/SiC on the microstructure and tribological characteristics of AA7075-based surface hybrid composites tailored using friction stir processing

“…Among these various processes, FSP has focused more attention on the microstructural modification of base matrix based on the principle of friction stir welding (FSW). [7][8][9][10][11] During this process, the material undergoes intense plastic deformation, which results in significant grain refinement. 12 Due to the formation of an ultrafine along with equiaxial grained structure during the refinement phase and reduced porosity level, the FSP technique has been employed for many industrial applications.…”

Development of a process envelope for friction stir welding of DH36 steel – A step change

“…There are many relevant optimisation studies for FSW of aluminium alloys including modelling, statistical analysis or experimental work, but they seem rather small scale projects when compared to the present work, and therefore cannot be transferred into FSW of steel. For example, Kumar et al [7] attempt to optimise the FSW of two dissimilar aluminium alloys with regard to tensile properties and hardness of the weld, with no commentary on the microstructural evolution of the thermo-mechanically affected zone. They [7] also explore the effect of each parameter (rotational speed, tool tilt and type of tool pin) on these properties by percentage contribution, as derived from their statistical analysis.…”

“…For example, Kumar et al [7] attempt to optimise the FSW of two dissimilar aluminium alloys with regard to tensile properties and hardness of the weld, with no commentary on the microstructural evolution of the thermo-mechanically affected zone. They [7] also explore the effect of each parameter (rotational speed, tool tilt and type of tool pin) on these properties by percentage contribution, as derived from their statistical analysis. Kumar et al [7] employ the Taguchi method to direct their analysis but this approach leads them to experimentally examine only nine sets of parameters; in fact, traverse speed, although highly significant, is not one of these parameters.…”

“…They [7] also explore the effect of each parameter (rotational speed, tool tilt and type of tool pin) on these properties by percentage contribution, as derived from their statistical analysis. Kumar et al [7] employ the Taguchi method to direct their analysis but this approach leads them to experimentally examine only nine sets of parameters; in fact, traverse speed, although highly significant, is not one of these parameters. Hence their conclusions are vague and limited.…”

Parametric studies on tensile strength in joining AA6061- T6 and AA7075-T6 by gas metal arc welding process

“…Taguchi approach is a robust design method that uses experimental design called orthogonal arrays (OAs). Taguchi method is to study a large number of decision variables with a small number of experiments [12,13]. By using and understanding the Taguchi method, welding quality and experimentation process were developed and improved.…”