摘要
目的提高切削刀具和耐磨零件的表面硬度和摩擦性能,延长工具的使用寿命。方法基于高功率脉冲磁控溅射技术(HiPIMS),在每个脉冲周期尾部施加反向正脉冲,控制ta-C沉积过程,通过电镜测试、拉曼测试、XPS测试、纳米压痕硬度测试、摩擦磨损实验分别分析脉冲频率、反向正脉冲能量对ta-C薄膜沉积速度、膜结构、硬度、结合强度、耐磨性能的影响。结果采用钨钢为基体进行实验,将频率从4000 Hz到1500 Hz依次降低,制备涂层。在频率为4000 Hz的处理条件下制备涂层时,ta-C膜层的厚度为479.2 nm,通过XPS可知,此时sp^(3)的原子数分数达到59.53%,硬度为32.65 GPa,且得到的薄膜在12.7 N时失效,耐磨性较差,摩擦因数约为0.163。在频率为1500 Hz的处理条件下制备涂层时,涂层各项性能均有所提升,ta-C膜层的厚度为488.6 nm,通过XPS可知,此时sp^(3)的原子数分数达到63.74%,硬度为40.485 GPa,且薄膜在14.9 N时失效,耐磨性较优,摩擦因数约为0.138。结论通过调节脉冲频率,可以有效提高ta-C薄膜的沉积效率,改善膜的结构和性能。随着沉积ta-C薄膜频率的降低,薄膜中sp^(3)的含量呈现增大趋势,摩擦因数也随之降低,有效改善了ta-C膜的耐磨性。
HiPIMS technology is a magnetron sputtering technology that uses higher pulse peak power and lower pulse duty cycle to produces high sputtering ionization rate,which has significant advantages in the application of hard coatings.Due to the problems in the discharge during HiPIMS deposition process,the coating performance is poor.The ta-C deposition process is controlled by applying reverse positive pulse at the end of each pulse period.The deposition rate,film structure,hardness,binding properties and wear resistance of ta-C film are effectively improved.YG6 tungsten cobalt carbide(size 19 mm×19 mm×5.5 mm)was deposited as the test material ta-C film,and the reverse voltage range of 50-550 V and the frequency range of 200-5000 Hz were applied at the tail of each pulse cycle by high-power pulse magnetron sputtering technology.For other process conditions,the main gas source was argon,the power was 5 kW,the matrix bias was−150 V,the fixed pulse width was 50μs,and the pulse frequency was set to 1500,2400,3200,4000 Hz,respectively.Then the furnace was heated and vacuumed,and the target was cleaned by ion etching.Then the transition layer was deposited according to the set procedure and finally ta-C was deposited.Each experiment lasted for 10 hours,and finally the sample was cooled at room temperature.Then,the surface cross section morphology of the ta-C thin film was observed by ZEISS Gemini 300 field emission scanning electron microscope,the bond bonding in the ta-C thin film was analyzed by laser Raman spectrometer,and the surface structure of the thin film was analyzed by X-ray photoelectron spectrometer.The hardness of coating was obtained by nano-indentation and the wear resistance of coating was obtained by UMT multifunctional friction and wear testing machine.For the ta-C film prepared by HiPIMS technology with reverse positive pulse,the optimal experimental equipment parameters were to set the pulse frequency to 1500 Hz,reduce the frequency from 4000 Hz to 1500 Hz successively to prepare the coating under the condition of 4000 Hz frequency treatment.The thickness of ta-C film was 479.2 nm.The content of sp^(3) could reach 59.53%by XPS.Its hardness was 32.65 GPa and the resulting film failed at 12.7 N.At this time,the wear resistance was poor,and the friction coefficient was about 0.163.Under the treatment condition of 1500 Hz,all the properties of the coating were improved,and the thickness of ta-C film was 488.6 nm.The content of sp^(3) could reach 63.74%by XPS.Its hardness was 40.485 GPa and the resulting film failed at 14.9 N.At this time,the wear resistance was also relatively excellent,and the friction coefficient was about 0.138.The results show that the pulse frequency can effectively improve the deposition efficiency of ta-C films,improve the structure and properties of the films.As the deposition frequency of ta-C films decreases,the content of sp^(3) bond in the films increases.The friction coefficient is also reduced,which effectively improves the wear resistance of ta-C film.
作者
何哲秋
冯利民
李建中
石俊杰
高宣雯
HE Zheqiu;FENG Limin;LI Jianzhong;SHI Junjie;GAO Xuanwen(Key Laboratory for Ecological Metallurgy of Multimetallic Ores,Ministry of Education,Northeastern University,Shenyang 110819,China;School of Metallurgy,Northeastern University,Shenyang 110819,China)
出处
《表面技术》
EI
CAS
CSCD
北大核心
2024年第13期96-103,共8页
Surface Technology
基金
国家重点研发计划(2019YFE0123900)。
