Application of Chromium-based Nitride Films to Cutting Tools.

通过在二元氮化物薄膜中引入第二金属，发展了亚稳态PVD薄膜，目的是获得优异的机械和摩擦学性能。阴极电弧法是一种专门用于制备亚稳态三元薄膜的方法，这种薄膜不能在稳定的热力学条件下合成。在2004-2006年的这一系列研究中，基于X射线衍射、扫描和透射电子显微镜分析的相变，研究了陶瓷氮化物膜的最大硬度。三元氮化物膜具有比二元氮化物膜更高的显微硬度，并且在一定值下具有它们自己的最大硬度。当<1-x>X=0.6时，Ti_ Al_xN的晶体结构由NaCl型转变为纤锌矿型，而Ti_<1-x>Cr_xN和Ti_<1-x>Zr_xN的晶体结构在所有X值下均保持NaCl型。Cr_<1-x>Al_xN和Zr_<1-x>Al_xN的显微硬度最大值出现在相界处，此处薄膜具有晶体和非晶混合的特殊结构。在（Ti，Al）N薄膜中加入Cr原子后，Al的最大溶解度提高到73 at.%无六方相偏析。研究了热退火制备的立方相Ti_xCr_yAl_zN薄膜的相变、晶格常数和显微硬度。它们在800℃时仍保持立方结构。薄膜的晶格常数比室温下降低了0.5%。在900℃以上的热扩散过程中，立方相部分转变为六方相，使其显微硬度降低。

Metastable PVD films have been developed by incorporating second metals to binary nitride films in aims a gaining excellent mechanical and tribological properties. The cathodic arc method is a specialized method in creating metastable ternary films which cannot be synthesized under stable thermodynamic conditions. In this series of study, 2004-2006, the maximum hardness of ceramics nitride films was investigated based on the phase transition analyzed by X-ray diffraction and scanning and transmission electron microscopy.Ternary nitride films had higher microhardness than the binaries and had their own maximum hardness at certain values. The crystal structures of Ti_<1-x>Al_xN changed from the NaCl-type to Wurtzite-type at the X=0.6, while the structures of Ti_<1-x>Cr_xN and Ti_<1-x>Zr_xN retained the NaCl-type for all X values. The maximum microhardness of Cr_<1-x>Al_xN and Zr_<1-x>Al_xN were obtained at phase boundary, where films had had some special microstructure with the mixture with crystal and amorphous. Addition of Cr atoms to (Ti, Al) N films expanded maximum Al solubility up to 73 at.% without hexagonal phase segregation. The cubic Ti_xCr_yAl_zN films obtained by thermal annealing were investigated with respect to phase transition, lattice parameter and microhardness. They were kept cubic type even up to 800℃. The lattice parameter of films at decreased by 0.5% compared with to that of room temperature. Finally, cubic phase was partially transformed into hexagonal phase through the thermal diffusion process over 900℃, which decreased its microhardness.