Study of grain growth and spark plasma sintering of nanocrystalline Cu powder

The sintering process of nanocrystalline copper(Cu) powder compacts was investigated by spark plasma sintering(SPS).The behavior and activation energy of the grain growth of the nano-Cu powder during SPS were analyzed.The microstructure and grain size were examined by SEM,FESEM and TEM.The results reveal that uniform and dense microstructures can be obtained under certain processing parameter conditions.It is the effect of pulsed current that improves the activity on grain surface,hence deduces the activation energy of grain growth considerably.The grain grows fast when the compacts are sintered.