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Compression resin transfer molding (CRTM), combining resin transfer molding (RTM) and compression molding, have been developed to fabricate fiber reinforced plastic (FRP) components with large dimensions or high fiber volume content. Although a lot of literature on CRTM is available, relatively little useful technical information is present regarding the proper choice of molding conditions for component optimization. The objective of this research is to investigate the effects of process variables, including injection pressure, mold opening distance, resin temperature, compression pressure, pre-heated mold temperature, and cure temperature, on the quality of CRTM products. The influence of these process variables on the part quality are investigated by applying Taguchi’s method. The ultimate stress measured by tensile test serves as an indicator of the part quality. Experimental result show that the compression pressure and the resin temperature are significant variables for improvements in the mechanical properties of the part, while the effect of pre-heated mold temperature on the mechanical properties appears to be trivial.

SUMMARY This experiment uses nickel electrodes and adds pulse potential and magnetic force when producing hydrogen via water electrolysis and explores how related parameters are affected by magnetohydrodynamics and pulse potential. Experiments showed that the Lorentz force of the magnetic field changes the direction of convective flow of the electrolyte, which affects the flow of bubbles during electrolysis. Adding a magnetic field increases the rate of current density by roughly 15% under a normal temperature, a distance of 2 mm between electrodes and a potential of 4 V. Pulse potential instantaneously increases current and accelerates both the movement of bubbles from the electrode surface and the mass transfer rate in the electrolyte, which lowers electrochemical polarization in the diffussion layer and further increases hydrogen production efficiency. When the duty cycle is 10% and the pulse on‐time is 10 ms, almost 88% of overall power is converted, and current density increases by 680 mA/cm2, which is an increase of roughly 38%. Generally, pulse potential and magnetic field effects enhance each other when added under suitable pulse potential and basic potential. Copyright © 2013 John Wiley & Sons, Ltd.