화학공학소재연구정보센터
Journal of the Electrochemical Society, Vol.145, No.8, 2827-2833, 1998
Characterization of flow-induced compositional structure in electrodeposited NiFe composition-modulated alloys
Flow-induced NiFe composition-modulated alloys (CMAs) are plated onto the disk of a rotating ring-disk electrode (RRDE) by oscillating the RRDE rotation rate during galvanostatic deposition. The relationships between processing and compositional structure in the electrodeposited CMAs are explored using an optimized potentiostatic stripping voltammetry technique, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. Results show that the CMA wavelength scales as the inverse of the flow oscillation frequency and the composition modulation amplitude are strongly affected by variations in both electrolyte flow oscillation frequency and amplitude. Fast Fourier transform analysis is used to probe the dynamic time scales of NiFe electrodeposition and to investigate the sensitivity of NiFe deposition to the oscillating electrolyte flow field. Results indicate that critical deposition chemistries occur over time scales much slower than those governing typical mass-transfer processes.