摘要
采用固定Ti间隔层厚度,改变Ti N层厚度的方法在Ti6Al4V合金表面制备Ti/Ti N多层膜,研究循环周期对Ti/Ti N多层膜的相结构、形貌特征、结合力、硬度和在模拟人体液中摩擦磨损行为的影响.结果表明,与Ti N单层膜相比,Ti/Ti N多层膜中Ti N由(111)择优取向转变为(200)择优取向,多层膜表面粗糙度、硬度和结合力得到显著改善.增加循环周期降低Ti/Ti N多层膜表面硬度,但有利于提高结合强度.多层Ti/Ti N膜的强韧化主要来自于Ti N层的细晶强化和界面共格强化效应.当Ti N与Ti层厚度比为30,循环周期为3时,Ti/Ti N多层膜具有良好的综合性能,硬度为15.8 GPa,结合强度为50 N,摩擦系数为0.35,体积磨损率低于4.0×10-6mm3/(N·m).
Ti and Ti alloys with low elastic modulus, good mechanical properties and biocompatibility have been widely used for dental implant, arthroplasty and internal fixation material in spinal fusion. But the poor wear resistance of Ti and Ti alloys generally results in the aseptic loosening of the implants. TiN coating has good chemical stability and biocompatibility in physiological environment and plays an important role in improving the corro- sion wear performance of Ti and Ti alloys. However, the adhesion strength of TiN film prepared by traditional technologies does not meet the requirement of long service life of the implants. In this work, the alternating Ti/TiN multilayer films were prepared by magnetron sputtering technology with constant Ti layer thickness and varying TiN layer thickness. The cycling periods were designed to be 1, 3, 6, 9, and 12. The total depositing time was 185 min. The main aims of this investigation were to clarify the effects of the cycling periods on the surface morphologies, hardness, bonding strength, friction and abrasion behavior in simulated body fluid of Ti/TiN multilayer films. The results show that the total thickness of Ti/TiN multilayer film is in the range of 5.5-6.0 μm. （111）tiN preferred orientation is found in TiN monolayer film, and （002）TiN preferred orientation is found in Ti/TiN multilayer films. In comparison with TiN monolayer film, Ti/TiN multilayer films exhibit lower surface roughness, higher hardness, bonding strength and wear resistance. The strengthening and toughening of Ti/TiN multilayer films result from the refinement of columnar crystals and interface coherent effect between Ti and TiN layer. The increase of cycling period decreases the hardness of Ti/TiN multilayer film, but is benefcial to enhancing the bonding strength to the substrate. The rupture and exfoliation of thin TiN layer at outer surface promote the abrasive wear and oxidation wear. At the condition of layer thickness ratio 30 for TiN and Ti and 3 cyc, the Ti/TiN multilayer film has good combined mechanical properties. Hardness is 15.8 GPa, adhesion strength is 50 N, coefficient of friction is 0.35, and volume wear rate in Hank＇s solution is less than 4.0×10^-6mm^3（N·m）.
出处
《金属学报》
SCIE
EI
CAS
CSCD
北大核心
2015年第12期1531-1537,共7页
Acta Metallurgica Sinica
基金
教育部科学技术研究重大资助项目313014~~
关键词
Ti/TiN多层膜
磁控溅射
循环周期
组织结构
磨损性能
Ti/TiN multilayer film, magnetron sputtering, cycling period, microstructure, wear resistance
