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The objective of this research is to examine the influence of low frequency pulsed electroforming process parameters, such as current, pulse-on time, pulse-off time, and electrolyte temperature, to obtain good thickness uniformity. For this purpose, a pulsed electroforming system was designed and made. Three level, four-parameter experiments were designed using Taguchi method. The effect of parameters and optimal parameters combination were obtained through signal-to-noise ratio (S/N), analysis of variance (ANOVA) and Pareto ANOVA method. Also the regression analysis was performed to obtain a predictive model. The results demonstrated that current has a dominant effect on thickness distribution and pulse-on time, temperature and pulse-off time affect thickness distribution, respectively. Optimum electroforming process parameters were determined and experimental tests were conducted to verify the optimized parameters. The results showed the effectiveness of the proposed optimization method.

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Transient liquid phase (TLP) diffusion bonding was carried out on nanostructured metal matrix composite sheets of Al-1100 alloy with 5 wt-% alumina particles at various bonding temperatures and process durations. A thin layer of 5 mm pure copper was electrodeposited as an interlayer. Joint formation was first attributed to the solid state diffusion of copper into the aluminium metal matrix followed by eutectic formation; then, base metal dissolution and isothermal solidification was completed at the joint interface. Joint area was characterised using scanning electron microscopy (SEM) and X-ray diffraction (XRD). Diffraction patterns showed the formation of intermetallic phases like CuAl 2 . The concentration of Al 2 O 3 particles increases across the interface as the bonding temperature increases. As a result, the highest bond strength of 123 MPa was achieved after a bonding duration of 30 min at 590uC.