Effect of Preteatment of Ammonia on the Nitriding Rate and Microstructure in Ion-nitriding

In this paper,the effect of various pretreatment of ammonia on the nitriding rate and structure of nitriding layer in ion-nitriding has been investigated by means of examination of optical microscope,micro-hardness and general ion-nitriding furnace.The result shows that the pretreatment of ammonia has distinct influence on the nitriding rate and structure.Especially,the best result can be attained by using ammonia which had been filtered and decomposed.