Optimum Welding Parameters for Friction Stir Welded AA6063 Pipe Butt Joint Using the Taguchi Method

Welding parameters for pipe joint friction stir welding (FSW) have been identified based on L-9 orthogonal arrays used in the Taguchi Method. Different welding parameters, such as rotation speed, travel speed and axial force, have been used to produce several quality friction stir welded AA6063 pipe butt joints. The reliability of products obtained in the FSW process can be improved through the identification of the optimum combination of welding parameters. Weld quality was evaluated based on its tensile strength and residual stress profiles. The S/N analysis and Analysis of Variance (ANOVA) have been used to determine significant welding parameters that affect weld quality. Maximum tensile strength with acceptable residual stress was obtained at the optimum welding parameters of 1300 rpm, 5 mm/s and axial force between 5 and 6 kN. The goal of this study was to optimize welding parameters for high tensile strength and low residual stress

Further validations of the hydrodynamic force coefficients for a laterally drifting ship in waves

Lateral drift effects are caused by the effects of wind forces and /or wave drifting forces acting on ships in actual seas Lateral drift effect has been found to have significant effects in the ship motion.(Faizul A. A. 2006). . The lateral drift effect are one of the effects that is included in the ship motion prediction to determine a good seakeeping performance of the ship.Another approach to determine the effects of lateral drift has been done in this project. The approach is by taking several sets of offset data at different drift angle. The new approach is named The Alternative Strip Method (ASM). The ASM will be another method to calculate the effects of lateral drift on the ship motion prediction. From the results obtained from the ASM calculations, the lateral drift effects are further verified on 2D/3D hydrodynamic force coefficients on floating body and 3D ship