Ti-6Al-4V基体上氮电弧熔化法制备TiN层的组织及性能

TiN layers prepared by nitrogen arc melting technique on Ti-6Al-4V substrate

采用直流氮电弧熔化方法在钛合金(Ti-6Al-4V)基体上原位制备了TiN表面层。采用扫描电子显微镜、X射线衍射和显微硬度仪等分析测试手段对TiN表面层的组织、硬度及摩擦磨损性能等进行了分析。探讨了电弧电流对TiN层组织及性能的影响。结果表明:通过氮电弧熔化法制备的TiN层组织为树枝晶,氮化层中树枝晶的含量随着深度的增加而减少,表面层与基体为冶金结合;随着电弧电流由60A增加到100A,所制备的TiN表面层中树枝晶的含量增加,表面层的硬度及耐磨性能都提高;当电弧电流为100A时,所制备的TiN表面层的最高硬度可达到1885HV,约为基体硬度的5倍,抗磨损性能也显著提高。

Direct current （ DC） nitrogen arc melting technique is presented,which allows for in-situ preparing TiN layers on Ti-6Al-4V substrate. The microstructures,hardness and wear properties of the TiN layers were investigated by scanning electron microscopy,X-ray diffraction and microhardness testing instrument. The effects of arc current on microstructure and properties of TiN layers were discussed. The TiN layer is mainly composed of TiN dendrites and the content of the TiN dendrites gradually decreased. The TiN layer has a good metallurgical bonding with substrate. With an increase of arc current from 60 A to 100 A,the amount of TiN dendrites increased,and the layer hardness and wear resistance enhanced. At the condition of 100 A,the TiN layer highest hardness reached 1885 HV which is about 5 times that of substrate. At the same time,the wear resistance of TiN layer was significantly increased.