The effect of starting nanostructure on the thermal stability of electrodeposited nanocrystalline Co

The effect of starting microstructure on the thermal stability of electrodeposited nanocrystalline Co was studied. The starting microstructure was characterized by X-ray diffraction, transmission electron microscopy, and infrared spectroscopy, while the thermal stability was investigated by differential scanning calorimetry. It was found that over the range of starting structures examined, 8–20 nm mean grain size and 240–980 ppm S, the S impurities have the dominant effect on the thermal stability. It was determined that the rate of abnormal grain boundary migration was controlled by dynamic segregation.