The Thermal Stability and Degradation Mechanism of Cu/Mo Nanomultilayers

The microstructural evolution of Cu/Mo nanomultilayers upon annealing was investigated by X-ray diffraction and transmission electron microscopy. The isothermal annealing process in the temperature ranges of 300-850 degrees C was conducted to understand the thermal behavior of the sample and follow the transformation into a nanocomposite. Annealing at 600 degrees C led to the initiation of grain grooving in the investigated nanomultilayer, and it degraded into a spheroidized nanocomposite structure at 800 degrees C. The sample kept the as-deposited Cu {111}//Mo{110} fiber texture up to 850 degrees C. The residual stress was investigated to explain microstructure changes. The activation energy of degradation kinetics of Cu/Mo nanomultilayers was determined to understand the rate-determining mechanism for the degradation of nanolaminate structures.