Ti6Al4V合金等离子体基氧离子注入层的层状结构

采用等离子体基氧离子注入技术对Ti6Al4V合金进行表面改性。注入负脉冲电压分别为10、20、30、40、50kV，注入剂量为0．6×10^17ions／cm^2。用XPS分析了注氧层中元素的分布和化学态。结果显示，注入电压增加，氧的浓度深度分布增加。注入氧元素的浓度深度分布曲线不同于束线式注入氧元素的类高斯分布，表面氧浓度最大，随着深度的增加出现一个略倾斜的氧浓度平台，该平台的宽度随注入电压增加而增加。氧离子注入引起基体元素Ti、Al、V的浓深分布发生变化，近表面区域Ti的原子百分含量减少，Al的含量增高，而V未检测到。并且随着注入电压的增加，近表面区域富集Al的浓度明显增加，富Al贫V的区域也明显加大。注入样品的改性层具有相似的层状结构，由表及里依次为表面污染层、TiO2和Al2O3组成薄的外层、内层在改性层中占的比例最大，由TiO2、Ti2O3、TiO、Ti、Al、Al2O3．V和VO组成。     

空气等离子体基注入Ti6Al4V合金摩擦学性能研究

采用空气等离子体基离子注入技术对Ti6Al4V合金进行了表面改性。注入负脉冲电压分别为10kV,30kV,50kV,注入剂量为0.6×1017ions/cm2。用X射线光电子能谱仪对注入层元素分布进行了分析,结果表明:改性层的外层为TiO2,外层与内层基体之间存在Ti2O3、TiO、TiN;采用球盘磨损试验机对注入层的摩擦学性能进行了研究。结果表明:随着注入电压的增加,摩擦因数减小,耐磨性能提高。且以50kV注空气最为显著,摩擦因数较基体降低了3倍多,磨损体积与比磨损率较基体均下降了1个数量级以上。注入层硬度比基材Ti6Al4V也有明显提高。     

氧等离子体离子注入Ti6Al4V表面强化研究

采用PⅢ对Ti6Al4V合金进行表面处理,温度控制在300～400℃之间,利用小掠射角X射线衍射技术（GXRD）、扫描电镜（SEM）研究不同工艺条件下的相结构和表面形貌,并且测量处理后试样的显微硬度、摩擦磨损性能。结果表明：试样表面形成了金红石相,且试样表面变得粗糙;在390℃处理后的试样硬度提高27％,抗磨损性能提高。     

6061Al合金等离子体基离子注氮表面的动态标度行为

利用原子力显微镜和掠入射X射线散射技术研究了6061Al合金等离子体注氮表面的粗糙度和标度行为。研究结果指出，注氮初期，表面粗糙度逐渐下降，当离子注入时间圉长时，表面粗糙度随注入时间的延长而逐渐增加，在远离平衡的条件下，材料的形成机制可通过分形理论研究，长时间离子注氮表面具有明显的分形特征，利用所得到的静态标度指数。生长指数和动态标度指数讨论了6061Al合金离子注氮表面的标度行为。     

铝合金表面氮和钛等离子体基离子注入改性层XPS研究

用XPS(X射线光电子能谱 )和GXRD(小掠射角X射线衍射 )研究了铝合金等离子体基离子注入氮再注入钛最后复合注入氮和钛改性层的成分分布及相结构 ,并用Gaussian Lorentzion峰位拟合方法分析了改性层中不同深度处各元素的化学态及其在相结构中的分布。结果表明 ,复合改性层的表层有较高浓度的氮和钛 ,次表层有较高浓度的钛及一定浓度的氮 ,铝 /钛界面有较宽的过渡区 ,基体中氮呈高斯分布。改性层主要由TiN ,TiO2 ,α Ti,TiAl3 ,Al2 O3 和AlN等组成 ,氮和氧还以固溶态的形式存在。最表层含有大量TiN及部分TiO2 ;次表层含有大量α Ti及许多TiN ;过渡层由TiO2 ,TiN ,TiAl3 ,Al2 O3 和AlN等组成 ;注氮层包括AlN ,Al2 O3 及α(Al)。各元素在相应相结构中的浓度分布与其成分深度分布基本相似。     

Al合金等离子体基离子注入形成AlN／DLC层结构研究

用X射线光电子能谱（XPS）和小掠射角X射线衍射（GAXRD）研究了铝合金LY12等离子体基离子注入N＋原位注入C形成AlN/DLC（类金刚石碳膜）改性层的成分分布及相结构,用激光Raman光谱分析了表面单一碳层的结构,对过渡层元素进行了Gaussian-Lorentzion峰位拟合分析。结果表明,N浓度在注入层呈Gauss分布,C浓度沿注入方向逐渐减小。C的注入使N分布有所拓宽。C在表面还能形成一层单一稳定的400nm的DLC膜。过度层主要由Al4C3,Al2O3,AlN,β-C3N4等组成。改性层总厚度达800nm。     

Ti6A14V合金等离子体基氧离子注入层的层状结构

采用等离子体基氧离子注入技术对Ti6A14V合金进行表面改性.注入负脉冲电压分别为10、20、30、40、50kV,注入剂量为0.6×1017 ions/cm2.用XPS分析了注氧层中元素的分布和化学态.结果显示,注入电压增加,氧的浓度深度分布增加.注入氧元素的浓度深度分布曲线不同于束线式注入氧元素的类高斯分布,表面氧浓度最大,随着深度的增加出现一个略倾斜的氧浓度平台,该平台的宽度随注入电压增加而增加.氧离子注入引起基体元素Ti、Al、V的浓深分布发生变化,近表面区域Ti的原子百分含量减少,Al的含量增高,而V未检测到.并且随着注入电压的增加,近表面区域富集Al的浓度明显增加,富Al贫V的区域也明显加大.注入样品的改性层具有相似的层状结构,由表及里依次为表面污染层、TiO2和Al2O3组成薄的外层、内层在改性层中占的比例最大,由TiO2、Ti2O3、TiO、Ti、Al、Al2O3,V和VO组成.     

真空退火对Ti6Al4V合金离子注氧层表面形貌和结构的影响

采用等离子体基氧离子注入技术对Ti6Al4V合金进行表面处理.注入电压选取- 50 kV,注入剂量为4.5×1017 ions/cm2.氧离子注入后对注入样品进行不同温度的真空退火处理.真空退火后,样品表面形貌发生显著变化.随着退火温度增加,先后出现点状、条状缺陷和浅白色块状区.500℃真空退火后样品表面粗糙度变化不大,600℃真空退火后样品表面粗糙度急剧增加.真空退火导致注氧层中氧流失,并且不能在注氧层中析出结晶相.     

Ti6Al4V合金表面离子注入N+C,Ti+N和Ti+C性能研究

采用等离子体基离子注入的方法在Ti6Al4V合金表面分别注入N+C、Ti+N和Ti+C元素,注入剂量均为2×1017 ions/cm2,N+C和Ti+N元素的注入负脉冲偏压为-50 kV,Ti+C元素的注入电压分别为-20 kV、-35 kV和-50 kV。通过X射线光电子能谱仪（XPS）和X射线衍射仪（XRD）对注入层进行了微观结构分析,结果表明：Ti+C注入层中存在TiC和Ti-O,Ti+N注入层中存在TiN和Ti-O键。采用纳米压痕仪和球盘磨损试验机对注入层的硬度和摩擦学性能进行了研究。结果表明：在相同注入电压下,Ti+C注入层的硬度最高,其次是Ti+N注入层,N+C注入层的硬度最低;Ti+C 注入层的硬度随着注入电压的增大而增大,最大硬度为11.2GPa。50kV注入层Ti+C具有最低的比磨损率,其值为6.7×10-5mm3/N.m,比磨损率较未处理Ti6Al4V基体下降了1 个数量级以上,表现出优异的耐磨损性能。     

Electrochemical behavior of the Ti6Al4V alloy implanted by nitrogen PIII

Plasma surface treatments have been used very often to enhance the surface properties of metallic materials. In this work, Ti6Al4V titanium alloy was treated by nitrogen plasma immersion ion implantation (NPIII) in order to obtain improvements in its surface properties, such as corrosion resistance evaluated here. The microstructure and corrosion behavior of the implanted and unimplanted samples were evaluated, using, XRD, GDOES and potentiodynamic polarization and impedance electrochemical spectroscopy tests in 0.6 M NaCl solution. It was verified that the NPIII created resistant layers to corrosive attacks. In corrosion tests by polarization, the implanted samples showed corrosion current density reduction of about 10 times compared to the Ti6Al4V alloy without treatment. Besides that, it was also observed a reduction of the passive current density of one order of the magnitude. In all the studied cases, the polarization curves were shifted to more positive values of potentials, indicating a lower tendency of these PIII treated surfaces to corrosion. The implantation process produced a thin TiN surface layer followed by Ti₂N and then a layer with nitrogen in solid solution, all detected by GDOES combined with X-ray diffraction. These layers promoted an excellent polarization resistance of the Ti6Al4V surfaces on impedance spectroscopy tests also. This better performance in these tests can be correlated with the formation of continuous nitride layer, which could retard chloride ions ingress into the substrate.     

Improved properties of Ti6Al4V by means of nitrogen high temperature plasma based ion implantation

A stable heating source, providing steady temperatures in the range of 200 to more than 1000 °C, was used to perform high temperature plasma based ion implantation (PBII) on Ti6Al4V. The precise control of the heating of the samples in vacuum while performing PBII is accomplished by means of an efficient electron source, working independent of the conditions of the discharge.The electrons produced by a low work function (2.1 eV) barium, strontium and calcium oxide cathode help with the start-up of the discharge, with the increase of nitrogen ionization and heating of the samples. The large growth of the treated layer thickness was a result of the thermal diffusion of nitrogen, reaching up to 20 μm, in the total process time lasting only 100 min. Experiments were run by setting a constant substrate temperature during PBII to 800 °C but varying the pulse intensity and the duration of the process. Our results showed improvements of the mechanical and tribological properties, and also higher resistance to corrosion of the samples treated by high temperature PBII.     

Ti6Al4V合金表面等电位空心阴极辉光放电W-Mo共渗层耐冲刷腐蚀性能

利用针状等电位空心阴极放电技术,在低于钛合金Ti6Al4V相变温度下,对其表面进行W-Mo共渗。利用扫描电子显微镜、X射线衍射仪、显微硬度计、球-盘摩擦磨损试验仪等分析了改性层的表面及截面形貌、相组成、显微硬度;及在室温干摩擦条件下的耐磨性能;利用冲刷腐蚀试验机研究了W-Mo合金渗层在单相流和双相流冲刷腐蚀条件下,在Na Cl腐蚀介质中的耐蚀性能。结果表明:Ti6Al4V基体经过W-Mo共渗处理后,在其表面形成了厚度约为25.0μm的合金改性层。合金层由Al MoTi_2和Ti_xW_(1-x)相组成。改性层的显微硬度高达850 HV0.1,较基体(450 HV0.1)显著提高,改性层的平均摩擦系数也从基体的0.30降到0.14。W-Mo合金渗层良好的表面力学性能有效的保护了基体材料不受外力的冲刷,在单相流冲蚀下,W-Mo合金渗层的腐蚀速度只是基体Ti6Al4V的1/19;在双相流冲蚀条件下,只是基体Ti6Al4V的1/37。     

Ti6Al4V钛合金表面激光合金化制备Ti-Cu合金层的组织结构

采用激光合金化技术在Ti6Al4V合金基体表面制备了厚度约为120 μm均匀致密连续的Ti-Cu合金层,分析了合金层的元素分布和显微组织结构。结果表明,Ti-Cu合金层中Cu元素随着合金层深度呈梯度分布,在靠近Ti-Cu合金层表面的区域主要是柱状晶夹杂着少量的块状晶,中上部区域主要是生长取向各异且较粗的不发达枝状晶和部分胞状晶,中下部区域主要是生长取向各异的胞状晶,合金层与基材的界面处主要以细小的平面晶为主。合金化层中Cu元素和Ti元素除了形成固溶体外,还形成了Ti₂Cu、Ti₃Cu和Cu₃Al₄等金属间化合物,同时还形成了Cu₃TiO₄和Al₂TiO₅等金属陶瓷相。     

Antibacterial property and bioadaptability of Ti6Al4V alloy with a silvered gradient nanostructured surface layer

In this paper,a silvered gradient nanostructured(GNS)layer was successfully fabricated on Ti6Al4V surface by means of surface ultrasonic rolling treatment(SURT)combined with silvering process.Surface characteristics,mechanical properties,corrosion resistance,antibacterial ability and cytotoxicity of GNS Ag/Ti6Al4V were investigated in comparison with those of coarse-grained(CG)and GNS Ti6Al4V samples.Owing to the greatly enhanced diffusion kinetics of Ag in the GNS layer,surface silvering on GNS Ti6Al4V was achieved at a relatively low temperature(500℃),and the release rate of Ag⁺was substantially accelerated,which endowed GNS Ag/Ti6Al4V with excellent antibacterial property.Moreover,improved wear and corrosion resistance of GNS Ag/Ti6Al4V can be achieved without cytotoxicity,indicating excellent bioadaptability.     

Improving tribological properties of Ti6Al4V alloy with duplex surface treatment

Ti-doped diamond like carbon films were deposited on both untreated and plasma nitrided Ti6Al4V alloy using Closed Field Unbalanced Magnetron Sputtering (CFUMBS) method and their tribological properties were evaluated by conducting sliding wear conditions. The influence of the nitrided layer on tribological behavior of Ti-DLC films was studied by means of XRD, SEM, scratch tester, microhardness tester and pin-on-disc tribotester. The microhardness results pointed out that the duplex treatment dramatically increased the surface hardness and reduced the plastic deformation of the alloy. Wear tests showed that Ti-DLC coatings on both untreated and nitrided surfaces caused a reduction in the coefficient of friction. The reason of the reduction in the coefficient of friction was found to be the formation of transfer film between the sliding surfaces. Wear rates demonstrated that wear resistance of duplex treated (Ti-DLC coating after nitriding) Ti6Al4V alloy was significantly improved.