It is difficult to improve the quality of friction stir welded joints of AA5052-H32 material because of scarce metrics on its concurrent optimization and prioritization. However, the objective of this article is to obtain optimal parametric values and identify important parameters using the Taguchi-Pareto method during the friction stir welding process of AA5052-H32 material. Then the ranks, delta values and optimal parameters are determined. The critical parameters identified for the friction stir welding process are the tool pin, rotational speed, welding speed and tool angle. When comparing the results of these parameters using the Taguchi method and Taguchi-Pareto method, the rotational speed retained its first position in both methods; the tool tilt angle gained the second position in the Taguchi-Pareto method from its third position when only the Taguchi method was considered. The welding speed became the third position in the Taguchi-Pareto method against the second position that it had in the Taguchi method. However, the tool pin profile retained its last position in both methods. Consequently, the rotational speed is the best parameter while the tool pin profile is the worst parameter. For the Taguchi-Pareto method, the optimal parametric setting is TPP2/TPP4RS1WS4TTA3. This is interpreted as cylindrical tapered or square tapered for the tool profile, 40 rpm of rotational speed, 75 mm/min of welding speed and 1.5° of tool tilt angle. The novelty of this study is the scope of analysis of the AA5052-H32 material that extends beyond the Taguchi method to the Taguchi-Pareto method where the concurrent optimization and prioritization of friction welding parameters are achieved.

A previous study has shown the successful application of the Taguchi method in both the direct and indirect perspectives to compute the optimal parameters during the turning of Inconel x-750 alloy. The study deployed signal-to-noise ratios to minimize the output of surface roughness, tool wear and cutting force but the machining economic parameters were not mentioned. Yet, the techno-economic dimension of machining aids profitable adjustments of the turning operations. To correct this deficiency, the present article introduces a techno-economic dimension to the turning process using literature data. This paper is about combining three variants of the Taguchi methods in five distinct formulations. The Taguchi, Taguchi-Pareto and Taguchi-ABC methods are combined with the present worth method by introducing the interest rate and inflationary rate at different points in the S/N ratio (SNR) calculations. Aspect ratios and direct parameter combinations replace the traditional direct parameter analysis in the factor-level framework. The present worth, optimal parametric setting and performance flow analysis are needed for all five formulations to ascertain the direction of performance analysis for the turning process. Concerning the direct and aspect ratios, the cutting velocity (PWV, 949.1444) and the feed rate-cutting velocity ratio (PWF/V, 0.026) are the first and last positions, respectively. Regarding the Taguchi experimental run, the present worth of the feed rate-cutting velocity ratio (PWF/V, -155.403) was the first position while the present worth of the cutting velocity (PWV, -185.009) is the last position. Results for other formulations show promising attributes for the methods. The work could be useful for planning purposes in turning operations.

The expanding proliferation of components for engineering applications requires greater optimisation of parameters, which consequently increases the need for more efficient boring practices. The Taguchi Pareto-Box Behnken design is an effective optimisation procedure for the process parametric optimisation of the IS 2062 E250 steel plates. However, the weakness of the Taguchi method in its inability to distinguish which parameters have greater effects on the boring process needs to be further suppressed. Consequently, this study investigates the coupling of the firefly algorithm to the Taguchi-Pareto-Box Behnken design method for the processing of the IS 2062 E250 steel plates during the boring operation. Linear programmes were developed for the problem formulation with two variants of the objective function definition. In the first variant, the Box Behnken design optimized parameters and the firefly-oriented optimisation procedure was addressed to attain optimal solutions. For the second variant, a regression equation was substituted as the objective function and the firefly procedure was implemented to obtain the optimal solutions. Based on a defined population for the problem, an initial test of convergence was actualized and 50 iterations were found as an effective convergence point for the iterations. Numerical simulation coupled with experimental data analysis was conducted to ascertain the effectiveness of the proposed method. Literature data on IS 2062 E250 steel plate processing on the CNC machine was used in the testing. The results revealed that the proposed method exhibits good performance for boring operations in machine shops. Using the Taguchi-Pareto-Box Behnken-firefly algorithm, the obtained results are promising. The application of this proposal would aid machining to better decisions that improve the quality of products and reduces the cost of production.