Are Direct Current Chromium Deposits Nanogranular?
C. Bishop, A. Jones & A. Rousseau Crystalline chromium from a variety of hexavalent chromium electrolytes, deposited using direct current conditions, was examined for grain size, grain uniformity, crystallographic texture, macro/micro stress and reduced modulus (Er), using focused ion beam (FIB), scanning x-ray diffraction (XRD) and nanoindentation (NI). Grain sizes of 10, 20, 50, 200 and 500 nm were observed for various plated chromium deposits and the existence of micro-ribbons of a different crystallographic orientation and crystalline size was postulated. The resulting data was compared with other XRD and TEM studies of chromium to determine whether deposits met the various criteria for being nanogranular. The continuously diffracting domain size of electrodeposited chromium, determined using XRD corrected for strong fiber orientation, indicated small domains on a nanogranular scale. Ion beam-enhanced secondary electron imaging using FIB suggested that very small granular regions c
