辉光等离子渗氮对纯钛铸件表面性能的影响

Plasma Nitridation and Mechanical Properties of Pure Titanium Casts

使用NH3在氮化炉中对纯钛铸件进行辉光等离子渗氮。分别应用X线衍射仪XRD、显微硬度计、扫描电镜、摩擦磨损实验及电化学实验研究等离子渗氮对纯钛铸件机械性能、摩擦学性能、耐腐蚀性的影响。铸造纯钛表面氮化处理后,颜色呈暗金黄色,表面由TiN、Ti2N相及氮在钛中的固溶体α-Ti(N)组成,显微硬度、耐磨性显著提高,在人工唾液中的耐腐蚀性亦明显提高。

The surfaces of pure titanium casts were modified with plasma nitridation in NH3 environment. The impacts of surface modification conditions,including the pressure,sample temperature and nitridation time etc. ,on the mechanical properties of the surfaces were studied. The microstmctures and properties were characterized with X- ray diffraction （XRD）, scanning electron microscopy （SEM） and conventional mechanical probes. The results show that the plasma nitridation significantly improves the properties of the Ti casts, and changes its stoichiometry. For instance, the modified Ti casts have much higher wear resistance, surface hardness, and corrosion resistance against the artificial saliva. And its color changed into dark-golden;the TiN,Ti2N and α-Ti（N） phases were observed in its surfaces.