NS163合金内氮化过程

Internal nitridation of NS163 alloy

在1050~1200℃温度范围内对NS163合金进行了内生氮化处理,通过氮化层深度随时间和温度的变化来表征氮化速率,并进行了NS163合金内生氮化过程的动力学分析。结果表明：氮化处理后获得了平行于表面的（Ti,Nb）N氮化物层,该氮化物有高温稳定、量大、细小和晶内弥散分布的特点;氮化层厚度与氮化时间之间满足抛物线关系;采用抛物线速率常K_p表征了不同温度的氮化速率,K_p随温度升高逐渐增大,二者满足Arrhenius型关系,表明内氮化过程受热激活过程控制;由此提出定量关系式来表达氮化层厚度与氮化时间和温度的关系。

The internal nitridation of NS163 alloy in an oxygen-free nitrogen atmosphere at 1050-1200 ℃ was carried out,and the nitridation rate was characterized by the variation of the nitriding layer depth with time and temperature,and the kinetics analysis of the nitriding process of the NS163 alloy was studied. The results show that after nitriding,the（ Ti,Nb） N nitride layer parallel to the surface is obtained, and the nitride presents good high-temperature stability, large volume, fine and good intragranular dispersion. The relationship between the thickness of nitride layer and the nitriding time is found to obey Wagner＇s parabolic law. The nitriding rate at different temperatures is expressed by the parabolic rate K_p. K_p increases gradually with the increasing of temperature,and there is an Arrhenius-type relationship between K_p and temperature,which indicates that the nitriding process is controlled by thermal activation process. A quantitative relationship between the thickness of nitrided layer and nitriding time and temperature is presented.