FCVAD技术制备CrCN薄膜的热稳定性研究

Study on Thermal Stability of CrCN Films Prepared by FCVAD Technology

磁过滤真空阴极弧沉积(FCVAD)技术制备的CrCN薄膜具有优异的机械性能,可作为表面改性膜应用于纺织器材、pcb钻头和活塞环中。本文针对薄膜因摩擦产生高温或应用环境温度高,其结构和性能将发生变化的情况,研究了CrCN薄膜的热稳定性。通过X射线衍射(XRD)、场发射扫描电子显微镜(FESEM)、拉曼光谱(Raman)和X射线光电子能谱(XPS)对常温至800℃下薄膜的结构进行了表征。结果显示:FCVAD技术制备的CrCN薄膜热稳定上限温度约为400℃。温度在400℃以下时,CrCN薄膜结构稳定,保持无序状态;当温度达到500℃时,薄膜表面出现细小晶粒,薄膜中的CrN相转化为Cr_(2)N相;随着温度继续升高,CrCN固溶相开始石墨化,薄膜内晶粒尺寸变大;当温度大于700℃时,薄膜中的碳以CO或CO_(2)的形式脱离薄膜,Cr元素以Cr_(2)O_(3)相的形式存在,并在800℃长成尺寸约400nm的晶粒。

CrCN films prepared by magnetic filtration cathodic arc deposition(FCVAD)technology have excellent mechanical properties and can be used as surface modified films in textile equipment,pcb drill bits and piston rings.In this paper,the thermal stability of CrCN films was investigated for the situation that the structure and properties of films will change due to high temperature caused by friction or high temperature of application environment.Structure of the films from room temperature to 800℃ was characterized by X-ray diffraction(XRD),field emission scanning electron microscopy(FESEM),Raman spectroscopy(Raman),and X-ray photoelectron spectroscopy(XPS).The results show that the upper limit of thermal stability of CrCN films prepared by FCVAD technique is about 400℃.When the temperature is below 400℃,the structure of CrCN films is stable and remains disordered.When the temperature reaches 500℃,fine grains appear on the surface of the films,and the CrN phase in the films is transformed into Cr_(2)N phase.As the temperature continues to increase,the CrCN solid solution phase starts to graphitize,and the grain size within the films becomes larger.When the temperature is greater than 700℃,carbon in the films leaves in the form of CO or CO_(2),and Cr element exists in the form of Cr_(2)O_(3) phase and grows into grains with a size of about 400nm at 800℃.