氮气流量对类富勒烯碳氮薄膜结构及力学性能的影响

目的在9Cr18钢表面制备类富勒烯碳氮薄膜,提高9Cr18钢表面强度。方法采用非平衡直流磁控溅射技术,在沉积温度为300℃的Ar和N2混合气氛中溅射C靶,制备类富勒烯CNx薄膜。利用XPS、Raman光谱、SEM研究了类富勒烯CNx薄膜的微观结构,利用纳米压痕仪和球盘摩擦试验机研究了CNx薄膜的力学性能和摩擦学性能。结果类富勒烯CNx薄膜中存在sp2 C—C、sp2 N—C和sp3 C—N化学键,类富勒烯结构的CNx薄膜的ID/IG比值较高且G峰向低峰位移动。随着氮气流量的增加,薄膜的硬度和弹性恢复系数先增大后减小,薄膜的硬度和弹性恢复系数越高,其磨损率越低。结论氮气流量为10 m L/min时制备的CNx薄膜具有较高的硬度和弹性恢复系数以及较低的摩擦系数和磨损率。在9Cr18钢表面制备类富勒烯碳氮薄膜能显著提高其表面强度。

Effects of N2 Gas Flow on Microstructure and Mechanical Property of Fullerene-like CNx Films

The work aims to enhance surface strength of 9Cr18 steel by preparing fullerene-like CNx films on the steel.The films were prepared by adopting applying DC magnetron sputtering technique to sputter target C in mixed Ar and N2 gas at 300 ℃.Microstructures of the CNx films were studied with XPS,Raman spectra and SEM,and mechanical property and tribological property of the films was studied with nanoindentor and ball-on-disk friction testing machine,respectively.There were sp2 C-C,sp2 N—C and sp3 C—N chemical bonds in the fullerene-like films.Peak G of the films shifted toward lower peaks due to higher ID/IG ratio.With N2 flow rate increased,hardness and elastic recovery coefficient first increased and then decreased.The higher the hardness and elastic recovery coefficient were,the lower the wear rate was.The CNx films prepared at N2 flow rate of 10 mL/min feature in higher hardness and elastic recovery coefficient,and lower friction coefficient and wear rate.Surface strength can be significiantly increased by preparing fullerene-like CNx films on the surface of 9Crl 8 steel.