Formation of Functionally Gradient cBN Films Using Ion Beam

采用IBAD法制备了氮化硼和/或ar混合离子的氮化硼薄膜。通过在界面处插入富b缓冲层作为可控缓冲层，制备了具有较好摩擦学性能的c-BN薄膜。缓冲层的摩擦学特性表明，B/N输运比越高的缓冲层具有最高的粘附强度和硬度值。在高速工具钢和WC等多种基体上形成的富b层上，可以成功地生长出具有高含量c-BN相的化学计量上层。缓冲层的加入对减小c-BN薄膜的内应力有显著的作用，并进一步增强了c-BN薄膜的摩擦学性能，从而在获得高硬度的同时获得高粘附强度。双层氮化硼薄膜在高温下对各种玻璃具有良好的耐腐蚀性能、高温相稳定性和化学内聚度。

Boron nitride films were prepared by IBAD with N and/or Ar-mixtured ions. The c-BN films with improved tribological properties has been approached by inserting a B-rich buffer layr as a controlled buffer at the interface. Tribological characterization of the buffer layr indicated that the films with higher B/N transport ratio exhibited the simultaneous achievement of the highest adhesion strength tigether with the highest hardness value. The stoicheometric upper layr with high fraction of c-BN phase could be successfully grown on the B-rich layr formed on various substrates including highspeed-tool steel and WC.The insertion of the buffer layr exhibited the significant effect on the reduction of internal stress of the c-BN films and further on the enhancement of the tribological properties to obtain high hardness simultaneously with high adhesion strength. The double-layred BN films exhibited excellent characteristics in anti-corrosion capability, high-temperature phase stability and chemical innertness against various glass at elevated temperatures.