Pr(NO_(3))_(3)掺杂对TC4微弧氧化涂层组织及性能的影响

Effect of Pr(NO_(3))_(3)doping on the organization and performance of TC4 micro-arc oxidation coatings

针对TC4钛合金的生物惰性和耐磨性差问题,采用一步法直接在钛合金表面合成含有生物活性羟基磷灰石的TiO_(2)涂层。在(CH_(3)COO)_(2)Ca-(NaPO_(3))6体系中掺杂微量稀土盐Pr(NO_(3))_(3),研究掺杂对TC4微弧氧化涂层的相组成、微观形貌、显微硬度、摩擦因数、涂层结合力等参数的影响。研究结果表明:通过电解液的优化,在(CH_(3)COO)_(2)Ca-(NaPO_(3))6电解液体系下通过微弧氧化涂技术能够在TC4合金表面直接生成含有羟基磷灰石(HA)的TiO_(2)涂层,有助于提高其生物活性;与未掺杂Pr(NO_(3))_(3)的涂层相比,适量掺杂后的微弧氧化涂层的显微硬度有所提高,当Pr(NO_(3))_(3)掺杂量达到1.0 g/L时,涂层显微硬度达到最大值,约为278.8±2.6HV1;同时获得涂层的摩擦因数最小,在0.25~0.35;当Pr(NO_(3))_(3)掺杂量达到1.5 g/L时,微弧氧化涂层的结合力最大,约为11.2 N左右,涂层的耐磨性最好。在微弧氧化液中适当引入Pr(NO_(3))_(3)掺杂能够提高涂层的耐磨性。

In view of the biological inertia and poor wear resistance of TC4 titanium alloy,in this paper,TiO_(2)coatings containing bioactive hydroxyapatite are synthesized directly on titanium alloy surface by a one-step method.The influences of Pr(NO_(3))_(3)doping on the phase composition,microstructure,microhardness,friction coefficient and coating adhesion of TC4 micro-arc oxidation coatings are studied by doping Pr(NO_(3))_(3)into(CH_(3)COO)_(2)Ca-(NaPO_(3))6system.The results show that TiO_(2)coatings containing hydroxyapatite(HA)can be directly generated on the surface of TC4 alloy by micro-arc oxidation coating technology in the electrolyte system of(CH_(3)COO)_(2)Ca-(NaPO_(3))6through electrolyte optimization,which is helpful to improve its biological activity.Compared with the coatings without doping Pr(NO_(3))_(3),the micro-hardness of the micro-arc oxidation coatings with appropriate doping content is improved.When the doping amount of Pr(NO_(3))_(3)reaches 1.0 g/L,the microhardness of the coating reaches the maximum value,which is about 278.8±2.6HV1.At the same time,the friction coefficient of the obtained coating is the smallest,between 0.25 and 0.35.When the doping amount of Pr(NO_(3))_(3)in the electrolyte reaches 1.5 g/L,the bonding force of the micro-arc oxidation coating is the highest at about 11.2 N,and the wear resistance of the coating is the best.The wear resistance of the coating can be improved by properly introducing Pr(NO_(3))_(3)doping into the micro-arc oxidation electrolyte.