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Incremental forming process is used to reduce the cost of sheet metal forming process when the low volume batches, customized parts or prototypes have to be manufactured. During recent years, some modifications were associated with this process to enhance formability, dimensional accuracy and product quality. In the present study, an experimental attempt was made to analyze formability of aluminum 1050 in two-point incremental forming process. Here, the effect of incremental forming parameters such as tool nose diameter, wall angle, spindle speed and deep step was studied on minimum thickness, surface quality, and springback. The obtained results showed that desirable thickness and corresponding formability are enhanced when the mandrel with lowest angle, i.e. 63° is utilized and tool tip diameter is 15 mm. It is also found that the increase in spindle speed causes reduction of formability due to exerting high temperature in the sheet material that increases thinning, while the increase in tool rotation improves both the dimensional accuracy and surface quality. Also, it was found that the increase in deep step and wall angle has a negative effect on quality characteristics. By performing multi-objective optimization through grey relational analysis, it is found that 15 mm tool nose diameter, 63° wall angle, 800 r/min spindle speed and 0.2 mm deep step are optimum parameter settings that cause 63% improvement in overall quality characteristic from initial parameter setting.

In this study, we present the optimization of end plates to produce uniform pressure and low content on the gas diffusion layer in polymer membrane fuel cell. For this purpose the end plates and the influence of parameters on the gas diffusion layer pressure has been investigated. Parameters studied are the thickness of the end plate, the depth of the bipolar plates groove and the clamping pressure applied to the end plates. After defining their values in the Abaqus finite element software, mechanical analysis has been carried out to examine the stress distribution on the gas diffusion layer and the results have been extracted. By extracting the results of the analysis and importing into the Adaptive Network-based Fuzzy Inference Systems in MATLAB software, a numerical relationship between the influential values and the outputs is extracted. By investigating these relationships and defining the objective function, we investigate the algorithm required for the equation and uniformity of stress distribution on the gas diffusion layer. In this research, the bee algorithm has been used and it has been evaluating the effective parameters of the optimum fuel cell state. After final review of the results, the suggested optimum state of the bee algorithm is the thickness of the end plate 12 mm, the depth of the bipolar plate groove is 0.1077 mm and the clamping pressure is 11.0199 MPa.

To achieve a defect-free butt joint of dissimilar metals by friction stir welding procedure, there are some major parameters, such as tool material and geometry, tool rotational speed, feed rate and tilt angel. This research is focused on dissimilar metals welding, namely 1100 Al alloy and 1045 carbon steel. In this paper, the effect of tool rotation speed and feed rate are experimentally investigated on surface appearance, microstructure and micro hardness of the friction stir welded plates. Optimum values of tool rotation speed and feed rate have been achieved experimentally by the quality of the butt joint.

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