Duplex Surface Treatment due to Combined ECR Plasma Nitriding and Ceramic Coatings

(1)采用高密度等离子体源，将2.45 GHz微波引入等离子体口，利用稀土磁铁通过石英窗产生尖端型磁场，制备电弧离子镀（AIP）体系。该等离子体端口设置在AIP设备真空室的上法兰上。在此实验室内，样品被放置在可加热至600ºC并偏置至-1 kV的台上。在该系统中进行了等离子渗氮和陶瓷涂层。(2)研究了TiN （Hv2200）和CrN （Hv2000）的氮化物膜、TiC （Hv3000）的碳化物膜、TiH_2 （Hv500）的氢化物膜、TiO_2 （Hv1200）的氧化膜和DLC （Hv2600）的类金刚石碳膜的力学性能。双相处理钢的力学性能如下：(1) TiN或crn包覆试样在重载条件下仍具有较好的耐磨性。(2)陶瓷膜大多具有良好的耐腐蚀性能。特别是TiH_2膜的腐蚀电流密度非常小。(3)双相处理试样的疲劳极限较未处理试样有较大提高。根据抗疲劳性能，氮化层的质量是最有效的。

(1) Production of Arc Ion Plating (AIP) system with high density plasma source2.45 GHz microwave was introduced into the plasma port where the cusp-type magnet field was generated by utilizing a rare earth magnet through a quartz window. This plasma port was set up at an upper flange of a vacuum chamber of AIP equipment. In this chamber, the specmens were mounted on the stage which could be heated up to 600ﾟC and biased untill -1 kV.Plasma nitriding and ceramic coating were done in this system.(2)Mechnical properties of duplex suraface treated steelsNitride films of TiN (Hv2200) and CrN (Hv2000), carbide film of TiC (Hv3000), hyderide film of TiH_2 (Hv500), oxide film of TiO_2 (Hv1200) and diamond like carbon film of DLC (Hv2600) were examined in this study. The mechanical properties of the duplex treated steels are as follows. (1) TiN or CrN-coated specimens after plasma nitriding showed the best wear resistance even under a heavy load. (2) Ceramic films showed good resistance tocorrosion mostly. Especially, we found the corrosion current density of TiH_2 film is very small. (3) The fatigue limit of the duplex treated specimens increased largely compared to that of the untreated one. The quality of the nitrided layr is most effective according to the fatigue resistance.