【摘要】 目的 对纯钛进行微波等离子体氮化处理，研究氮化工艺参数中的微波等离子体氮化功率对氮化层微观结构和性能的影响，以提高纯钛表面的硬度并改善其耐磨性。方法 采用微波等离子体化学气相沉积技术，在微波功率为4 250、4 500、4 750、5 000 W的条件下，对纯钛表面进行氮化处理。采用X射线衍射仪分析氮化层的物相结构，采用扫描电子显微镜观察氮化层表面和截面的形貌特征，并测量氮化层厚度。通过维氏硬度计和纳米压痕仪测定氮化层的硬度，并通过摩擦磨损测试对材料的耐磨性能进行表征。结果 在较低微波功率（4 250 W）条件下，等离子体的浓度和活性很低，钛表面出现了Ti N_0.3相，仅形成较薄的氮化层。随着功率的增大，等离子体的活性和密度增强，扩散机制发生转变，形成了Ti₂N和Ti N双相结构，氮化层厚度随之增大，从而提高了氮化层的硬度，并提高其耐磨性。在5 000 W微波功率下制备的氮化层表现出最佳性能，硬度达到22.84 GPa，摩擦因数仅约为0.1。结论 微波功率的变化显著影响基体表面微波等离子体的浓度和活性，进而改变氮化层的物相、结构和性能。更多还原

【Abstract】 The work aims to perform microwave plasma nitriding on pure titanium and investigate the effects of microwave plasma nitriding power, as a process parameter, on the microstructure and properties of the nitride layer, so as to enhance the surface hardness of pure titanium and improve its wear resistance. Microwave plasma chemical vapor deposition was employed to nitride the surface of pure titanium under microwave powers of 4 250, 4 500, 4 750, and 5 000 W. X-ray diffraction was used to analyze the phase composition of the nitride layer, and scanning electron microscopy was employed to observe the surface and cross-sectional morphologies of the nitride layer and measure its thickness. The hardness of the nitride layer was evaluated with a Vickers hardness tester and a nano-indentation instrument and the wear resistance was assessed through friction and wear tests. At a lower microwave power of 4 250 W, the plasma concentration and activity were relatively low, leading to the formation of a thin nitride layer containing TiN_0.3. As the power increased, the plasma activity and density were enhanced, resulting in a transition of the diffusion mechanism and the formation of a dual-phase structure comprising Ti₂N and TiN. This also led to an increase in the thickness of the nitride layer, thereby improving its hardness and wear resistance. The nitride layer prepared at 5000 W exhibited optimal performance, with a hardness of 22.84 GPa and a friction coefficient of approximately 0.1. Variations in microwave power significantly affected the concentration and activity of the plasma on the substrate surface, thereby affecting the phase composition, structure, and properties of the nitride layer.更多还原