【摘要】 采用双层辉光离子渗金属技术进行钛(TA2)及钛合金(TC4)的等离子渗Nb表面改性研究。分析了合金化条件对渗层Nb含量及厚度的影响,在此基础上得到优化的典型工艺条件。研究发现,在1 000℃进行合金化时,放电气压对渗层表面Nb含量有显著的影响,在本试验选取的气压范围(20～80Pa)之内,气压为65Pa时可以得到最佳质量的渗层。对此典型条件下渗层的组织形貌及成分分布特征进行了观察与分析,测试了渗层的显微硬度并用划痕法评价了渗层结合强度。结果表明,渗层表面Nb含量可达70%左右,向内逐渐降低,呈梯度分布特征。渗层与基体结合良好,硬度显著提高。更多还原

【Abstract】 Titanium plasma Nb alloying was studied by double glow discharge plasma surface alloying process. Alloying condition’s impacts on Nb content and thickness of alloying layer were analyzed. On this basis, optimized process conditions are obtained. The results show that discharge pressure has significant impact on Nb content of alloying layer. Ranging from 20 to 80Pa , the optimal alloying layer can be obtained at 65Pa. Observations and analyses are carried out to micro-structure and distribution of elements in the alloying layer under the typical processing condition. Micro-hardness is tested, and bond strength of alloying layer is evaluated with scarification. The results indicate that Nb content of alloying layer is up to 70% and descends gradually from surface to center, alloying layer and matrix are well combined, and hardness is evidently enhanced.更多还原