Electroforming is a specific use of electroplating (electro deposition) for production of metal parts. In this process that is also called “the art of growing parts”, metal anode solves as ion in electrolyte solution and deposit on cathode (mandrel) surface. After reaching to specific thickness of deposition, the deposition will be separated from the mandrel surface and is behaved as an independent part. However, when requirements specify high tolerances, complexity, lightweight and miniature geometry, electroforming is a serious contender process. In this project after designing and preparing the setup for producing bellows with electroforming process a series of primary experiments to select the effective parameters of process were conducted. These experiments were used as a part of Taguchi experiment design procedure. Four factors under low frequency electroforming condition namely, current density, temperature, on time and off time each in three levels were selected as control factors. After conducting experiments and producing samples, thickness of these samples were measured at various points by use of optical microscope and image processing software and thickness standard deviation for each sample were calculated. By use of the data analysis (analysis of variance) in Taguchi method and Pareto ANOVA analysis, effect of each factor and their optimum level was achieved. A regression equation that is the estimation equation between input and output values was also modeled with MINITAB software. Results of analysis shows that the current density factor is the dominate factor for this process. Also on time, Temperature and off time are effective on thickness standard deviation, respectively. For verification of optimization an experiment with factors at the optimum level was conducted and minimum thickness standard deviation was achieved. Finally, by using of two software, ANSYS and COMSOL, primary current density on cathode (mandrel) surface was simulated and relative values for primary current density and thickness was compared with each other. Results show that relative thickness distribution for electroformed part is largely dependent on primary current density distribution on mandrel surface. Key Words: Electroforming, Thickness Standard Deviation, Taguchi Design of experiment, Simulation.
