中文摘要：

以热等离子束作为等离子源，以氮气、氢气混合气体作为工作气体，对工业纯钛进行表面渗氮处理，并利用显微硬度仪、X射线衍射仪、扫描电镜、金相显微镜分别对氮化后试样进行显微硬度测定、相结构及断面形貌分析。结果表明：在等离子束对试样进行15min的照射后即可在工业纯钛（TA2）表面获得具有一定厚度的硬度较高的氮化层。

英文摘要：

Titanium and titanium alloys have some very attractive properties enabling them to be used in aerospace applications. Nitriding of titanium and titanium alloys has been investigated for many years and is used effectively for protection against wear. In this research we report the results obtained from plasma jet nitriding of titanium TA2 and explore the nitriding mechanisms. The influence on the properties of the surface layers inthe thermal plasma jet nitriding process was thoroughly studied by many techniques, respectively X-ray diffraction （XRD）, scanning electron microscopy （SEM） and optical microscope. It is found that there is an increase of the hardness after nitriding due to the formation of new phases like TiN and Ti2N on the surface of the titanium TA2. These results show that the reaction speed of the. thermal plasma irradiation is much higher than that of traditional plasma nitriding process.