Stability studies of iron particle

Commercial 1500 Oe iron particles were studied for environmental stability. The powders were subjected to different environmental conditions up to six months to determine the effects of temperature, humidity and air/nitrogen on the stability of the particles. Results showed that long term stability of iron particles was affected by the storage conditions. The oxidation rate of the particles in air was accelerated with increasing temperature and humidity. The particles also became unstable during extended storage in nitrogen at elevated temperatures. A surface study was carried out in which the iron particle sample was heated to 300°C in the vacuum chamber and the chemical states of iron were monitored by XPS. More metallic iron was observed at particle surface after heating. This could be the reason for particle instability under nitrogen storage at elevated temperatures.