电弧离子镀TiN/Ti纳米多层膜的力学性能

采用多弧离子镀技术,在不同沉积参数下合成具有纳米调制周期的TiN/Ti多层膜。利用X射线衍射仪(XRD)、扫描电子显微镜(SEM)、XP-2台阶仪、XP型纳米压痕仪、X射线能谱仪(EDS)研究了调制周期对TiN/Ti纳米多层膜微观结构、表面形貌以及力学性能的影响。结果表明,膜层由TiN和Ti交替组成,不存在其它杂相,且TiN薄膜以面心立方结构沿(111)密排面择优生长;TiN/Ti多层膜外观致密、平滑、颜色均匀金黄,随着调制周期的减小,薄膜表面大颗粒数量和尺寸均减小,且氮含量逐渐升高,膜层硬度呈现出增大的趋势。     

调制结构对TiN/ZrN纳米多层膜的表面形貌、生长行为及力学性能的影响

利用射频反应磁控溅射方法,设计并制备了一系列不同调制周期的TiN/ZrN纳米多层膜.利用原子力显微镜、X射线衍射仪和纳米压痕仪对多层膜的表面形貌、微观结构和力学性能进行了系统表征.研究结果表明调制结构影响着薄膜的择优生长取向、沉积速率和表面形貌;在调制周期为7nm～26nm的范围内,随调制周期的增加,TiN/ZrN多层膜的织构取向有从(100)面向(111)面转变的趋势;TiN和ZrN层的沉积速率随调制周期的变化而变化.在调制周期为15nm左右时,表面粗糙度最小,减小和增加调制周期均导致粗糙度的增加.力学性能分析表明TiN/ZrN多层膜的硬度和弹性模量均高于单一TiN和ZrN的硬度和弹性模量,且随着调制周期的减小有逐渐增加的趋势.此外,根据调制结构和力学性能的分析结果,讨论了TiN/ZrN纳米多层膜的硬化机制.     

TiN/TiCN多层调制结构薄膜的耐蚀性

多弧离子镀和磁控溅射制备薄膜各有优缺点,将2种技术复合制膜的研究还少有报道.采用多弧离子镀和磁控溅射复合技术在304不锈钢基体表面制备了TiN单层和TiN/TiCN多层膜,采用扫描电镜、X射线衍射仪并结合电化学测试等着重研究了不同调制周期下薄膜组织结构与耐腐蚀性能的变化规律.结果表明:所制备的TiN/TiCN多层膜表面平整、致密,随着调制周期的减小,TiN/TiCN多层膜发生生长取向的转变,且具有(111)晶面生长织构;TiN/TiCN多层膜在3.5 ％NaC1溶液中的抗腐蚀能力优于基体和单层TiN薄膜,随着多层膜调制周期的减小,其抗腐蚀性逐渐增强,在λ =0.150 μm时,多层膜的自腐蚀电流密度和极化电阻分别为0.106 7μA/cm2和679.700 kΩ·cm2,腐蚀速率下降到最低,具有良好的耐腐蚀性.     

铝基复合材料表面多层复合厚膜的研究

对含50%AlN颗粒的铝基复合材料进行预处理后,在其表面依次采用浸锌化学镀镍工艺制备Ni-P过渡层,采用脉冲偏压磁过滤多弧离子镀工艺沉积硬质Ti/TiN调制周期膜,采用脉冲等离子体化学气相沉积工艺制备含氢类金刚石(DLC)膜等工艺最后形成了多层复合薄膜体系。利用X射线衍射仪、扫描电子显微镜、光谱仪、原子力显微镜、微载荷显微硬度仪、摩擦磨损试验机等设备分析了复合薄膜的组织结构、膜层形貌、截面形貌、显微硬度和摩擦系数等性能特点。测试表明:铝基复合材料/Ni-P层/Ti/TiN调制周期膜/含氢DLC膜这一梯度膜系具有结构交替变化,相邻界面形成混合层,性能梯度分布,硬度逐渐增加,摩擦系数小的特点。该复合工艺能够有效地解决铝基复合材料上制备硬质厚膜的热适配和晶格错配度大的难题,制备薄膜具有良好的膜基结合性能。     

TiN/AlN纳米多层膜的调制周期及力学性能研究

采用一种新型的离子束辅助非平衡反应磁控溅射设备制备了TiN/AlN纳米多层复合膜.采用XRD衍射、TEM、显微硬度计和干涉显微镜对TiN/AlN纳米多层膜的微结构和力学性能进行了表征.结果表明TiN/AlN多层膜有良好的周期;调制结构影响薄膜的择优取向,薄膜整体表现出硬度增强的效果,硬度随调制周期的变化而变化并在调制周期为7.5 nm时达到最大值.     

Ti掺杂及Ti应力缓和层对类金刚石薄膜附着力的影响

研究了Ti掺杂对磁控溅射类金刚石(DLC)薄膜附着力及硬度的影响,同时在Ti掺杂类金刚石(Ti-DLC)薄膜的基础上,通过引入Ti应力缓和层制备了Ti/Ti-DLC/Ti/Ti-DLC……软硬交替多层薄膜,研究了Ti应力缓和层对进一步提高薄膜附着力特性的作用.采用纳米划痕仪和显微硬度计分析测试了薄膜的附着力和硬度.研究表明,金属Ti的掺杂有利于DLC薄膜附着力特性的改善,但对硬度有一定的影响.Ti应力缓和层的导入进一步改善了Ti-DLC薄膜的附着力特性,使其达到或超过了TiN薄膜的水平,对于附着力的改善Ti应力缓和层存在最佳的厚度值.采用特殊的变周期多层结构设计即在应力集中的膜基界面附近采用较小的调制周期,薄膜项层附近采用较大的调制周期不但可以保持足够的附着力,还可维持Ti-DLC薄膜原有的硬度.     

调制比对电弧离子镀Cr/TiN纳米多层膜力学性能的影响

采用电弧离子镀技术,通过改变调制比沉积Cr/TiN纳米多层膜。利用扫描电子显微镜、原子力显微镜、X射线衍射仪、纳米压痕仪研究了调制比对Cr/TiN纳米多层膜表面形貌、微观结构以及力学性能的影响。结果表明,纳米多层膜表面致密、平滑均匀,膜层与基底结合良好,膜层综合力学性能优异,出现明显的纳米效应和界面效应。当调制比为2∶3时,纳米多层膜的硬度达最大值33.22GPa。     

非对称双极脉冲反应磁控溅射制备TiN/NbN多层膜

采用非对称双极脉冲磁控溅射制备了一系列不同调制周期的TiN/NbN纳米多层膜,利用X射线衍射分析(XRD)、纳米压痕仪、扫描电子显微镜(SEM)表征了薄膜的微观结构、力学性能和断口形貌。结果表明,在调制周期为19.86nm时,纳米压痕硬度达到43GPa。利用三点弯曲法形成裂纹的扩展,并观察到了裂纹的偏转特征。     

多弧离子镀与磁控溅射共沉积TiN/TiCN多层膜的高温抗氧化性能

TiN/TiCN多层膜的高温抗氧化性研究对于扩大其应用领域具有重要作用,但目前鲜见相关报道。采用多弧离子镀与磁控溅射技术以不同调制周期在304不锈钢表面共沉积TiN/TiCN多层膜。采用XRD、XPS、倒置显微镜及高温氧化试验研究了多层膜的高温抗氧化行为。结果表明:TiN/TiCN多层膜表面光滑平整、均匀致密,薄膜主要为具有Ti-(C,N)键的fcc-TiN结构;随着调制周期的减小,TiN/TiCN多层膜生长取向发生转变,且具有(111)晶面生长织构;随着氧化温度的升高,多层膜的显微硬度逐渐降低,氧化增重速率不断增大,且在700℃之后变化速率较快,薄膜的开始氧化温度约为750℃;随着调制周期的减小,多层膜TiN与TiCN界面层数量增多,促使晶粒细化,提高了其致密性,还隔断了缺陷贯穿薄膜的连续性,显著降低了薄膜的孔隙率,致使O原子扩散困难,增强了薄膜的高温抗氧化性能。     

TiN／NbN纳米多层薄膜的交变应力场和超硬效应

为了研究纳米多层薄膜的超硬效应，采用反应溅射法制备从1.4nm至27nm不同调制周期的一系列TiN/NbN纳米多层膜。高分辨电子显微镜参薄膜的调制结构和界面生长方式的观察发现，TiN/NbN膜具有很好的调制结构，并呈现以面心立方晶体结构穿过调制界面外延生长的多晶超晶格结构特征。显微硬度测量表明，TiN/NbN纳米多层膜存在随调制周期变化的超硬效应。薄膜在调制周期为8.3nm时达到HK39.0 Gpa的最高硬度。分析认为，两种不同晶格常数的晶体外延生长形成的交变应力场，对材料有强化作用，这是TiN/NbN纳米多层膜产生超硬效应的主要原因。     

Bactericidal and biocompatible properties of TiN/Ag multilayered films by ion beam assisted deposition

Nanoscale TiN/Ag multilayered films of thickness 500 nm were synthesized on AISI317 stainless steel by ion beam assisted deposition (IBAD) with the modulation period of 4, 5, 6, 7.5, and 12 nm. The bactericidal and biocompatible properties of TiN/Ag multilayered films were investigated through Gram negative E. coli bacteria and L929 cells (mice fibroblast) as well as human umbilical vein endothelial cells (HUVEC). The results show that the TiN/Ag multilayered films with the modulation period of 7.5 nm possess the strongest bactericidal property. The cytotoxicity grade of TiN/Ag multilayered coating with the modulation periods of 7.5 nm, 12 nm is in 0-1 scope, which indicates this film has no cytotoxicity to L929. HUVEC on TiN/Ag multilayered film grows well and shows good cellularity. Auger electronic spectroscopy reveals the relationship between the structure of TiN/Ag multilayered film and the biomedical properties.     

Bactericidal and biocompatible properties of TiN/Ag multilayered films by ion beam assisted deposition

Nanoscale TiN/Ag multilayered films of thickness 500 nm were synthesized on AISI317 stainless steel by ion beam assisted deposition (IBAD) with the modulation period of 4, 5, 6, 7.5, and 12 nm. The bactericidal and biocompatible properties of TiN/Ag multilayered films were investigated through Gram negative E. coli bacteria and L929 cells (mice fibroblast) as well as human umbilical vein endothelial cells (HUVEC). The results show that the TiN/Ag multilayered films with the modulation period of 7.5 nm possess the strongest bactericidal property. The cytotoxicity grade of TiN/Ag multilayered coating with the modulation periods of 7.5 nm, 12 nm is in 0–1 scope, which indicates this film has no cytotoxicity to L929. HUVEC on TiN/Ag multilayered film grows well and shows good cellularity. Auger electronic spectroscopy reveals the relationship between the structure of TiN/Ag multilayered film and the biomedical properties.     

TiN／AIN纳米多层膜的调制周期及力学性能研究

采用一种新型的离子束辅助非平衡反应磁控溅射设备制备了TiN／AlN纳米多层复合膜。采用XRD衍射、TEM、显微硬度计和干涉显微镜对TiN／AlN纳米多层膜的微结构和力学性能进行了表征。结果表明：TiN／AlN多层膜有良好的周期；调制结构影响薄膜的择优取向，薄膜整体表现出硬度增强的效果，硬度随调制周期的变化而变化并在调制周期为7、5nm时达到最大值。     

TiN/TiC multilayer films deposited by pulse biased arc ion plating

TiN/TiC multilayer films were deposited on high-speed-steel (HSS) substrates using pulse biased arc ion plating. For comparison, TiN and TiC films were also deposited. Scanning electron microscopy (SEM), X-ray diffraction (XRD) and Auger electron spectroscopy (AES) were applied to investigate the modulation period thickness, microstructure and content depth distribution of the films, respectively. And microhardness and film/substrate adhesion were also analyzed using knoop tester and scratching method. The results showed that the multilayer films with different modulation period of 40-240 nm exhibit a modulation structure and the interface width is about 20∼30 nm. Microhardness of the multilayer films were not obviously improved compared to that of TiN and TiC film, and the reason was analyzed. In comparison to TiN film, film/substrate adhesion values of the multilayer films were deteriorated with the increasing of modulation period due to the brittle characteristics of TiC film.     

The microstructure and mechanical properties of TaN/TiN and TaWN/TiN superlattice films

The microstructure and the microhardness of the TaN/TiN and TaWN/TiN superlattice films have been studied with X-ray diffraction, transmission electron microscopy and microhardness tester. The results showed that both TaN/TiN and TaWN/TiN superlattice films have a cubic crystal structure with an epitaxially grown mode of polycrystallinity. Lattice constants of superlattice films are between those of the constituent materials. The superhardness effect was found in TaN/TiN and TaWN/TiN superlattice films and the maximum hardness value was 40.0 GPa at a modulation period of 9.0 nm for TaN/TiN, and 50.0 GPa at a modulation period of 5.6 nm for TaWN/TiN. It is proposed that the lattice mismatch affects the microhardness value and the peak position of maximum hardness. The inhibition of dislocation motion by alternating stress fields of interfacial coherent strains is believed responsible for hardness anomalies.     

NiTi合金上沉积氮化碳薄膜的力学和血液相容性研究

采用磁控溅射法在生物医用NiTi合金基体表面制备了Ti/CN_x（x≈0.26）梯度薄膜,并制备了Ti/类金刚石(DLC)以及Ti/TiN薄膜进行对比研究. 利用显微硬度计、划痕仪比较分析了上述各薄膜的力学性能,通过表面接触角法研究了薄膜的亲水性. 着重测试并分析了溶血率和血小板粘附行为,进而对薄膜的血液相容性进行评估. 结果表明：Ti/CN_x梯度薄膜与NiTi合金基底的结合牢固,结合力达到63.6N. Ti/CN_x薄膜硬度为23.01GPa,和Ti/TiN薄膜硬度相当,略高于Ti/DLC薄膜. 溶血率和血小板粘附试验表明,Ti/CN_x梯度薄膜能有效改善NiTi合金基底的亲水性和血液相容性,与Ti/TiN和Ti/DLC薄膜相比,Ti/CN_x梯度薄膜具有最小的溶血率,仅为1.12％,并且无论在血小板的粘附数量还是在血小板变形程度都最少,因此具有良好的血液相容性.     

Influence of Ti/TiN bilayered and multilayered films on the axial fatigue performance of Ti46Al8Nb alloy

The effects of Ti/TiN bi- and multilayered films on the fatigue performance of the Ti46Al8Nb alloy were investigated. Ti/TiN films with a total thickness of 1 μm were deposited on the Ti46Al8Nb alloy substrate by the hollow cathode deposition method. The samples were examined with various analytical techniques including nanoindentation, scratch test, stripping layer substrate curvature test and scanning electron microscopy. The results show that multilayered Ti/TiN films can enhance the fatigue strength of the Ti46Al8Nb alloy, whereas bilayered films have no obvious effect. Compared with the bilayer, the multilayer exhibits higher hardness, higher residual compressive stress and higher adhesion strength to the substrate. It is also demonstrated that the multilayer is responsible for retarding fatigue crack growth. All the superior properties make the hard Ti/TiN multilayer to be an effective protection coating for the enhanced fatigue strength of the brittle substrate.     

Tribological and mechanical behaviors of TiN/CNx multilayer films deposited by magnetron sputtering

TiN/CN_x multilayer films with bilayer periods of 4.5-40.3 nm were deposited by direct-current magnetron sputtering. Layer morphology and structure of the multilayered films were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy and transmission electron microscopy. The TiN/CN_x multilayers exhibited coherent epitaxial growth due to the mutual growth-promoting effect at small bilayer period and some crystalline regions going through the interface of TiN/CN_x. Nanoindentation tests showed that the hardness of the multilayers varied from 12.5 to 31 GPa, with the highest hardness being obtained with a bilayer period of 4.5 nm. The tribological properties of the films were investigated using a ball-on-disk tribometer in humid air, and the TiN/CN_x multilayer with a bilayer period of 4.5 nm also exhibited the lowest friction coefficient and the highest wear resistance.     

Structure,hardness and tribological properties of nanolayered TiN/TaN multilayer coatings

TiN/TaN coatings, consisting of alternating nanoscaled TiN and TaN layers, were deposited using magnetron sputtering technology. The structure, hardness, tribological properties and wear mechanism were assessed using X-ray diffraction, microhardness, ball-on-disc testing and a 3-D surface profiler, respectively. The results showed that the TiN/TaN coatings exhibited a good modulation period and a sharp interface between TiN and TaN layers. In mutilayered TiN/TaN coatings, the TiN layers had a cubic structure, but a hexagonal structure emerged among the TaN layers besides the cubic structure as the modulation period went beyond 8.5 nm. The microhardness was affected by the modulation period and a maximum hardness value of 31.5 GPa appeared at a modulation period of 8.5 nm. The coefficient of friction was high and the wear resistance was improved for TiN/TaN coatings compared with a homogenous TiN coating, the wear mechanism exhibited predominantly ploughing, material transfer and local spallation.     

热氧化对钛合金表面氧化层的影响

对钛合金Ti6Al7Nb(以下简称TAN)和Ti6Al4V(以下简称TAV)通过热氧化处理获得表面氧化层,用金相显微镜、维氏硬度计、XRD和XPS等手段对氧化层的性能进行表征。结果表明:相同氧化温度和氧化时间,TAN合金较TAV合金表面形成的氧化层更薄、致密度更好;合金表面硬度随热氧化温度的升高和氧化时间的延长而增加,但温度过高(TAN:1000℃;TAV:900℃)会使氧化层疏松多孔,硬度反而会下降;通过XPS对不同温度短时间氧化样品进行表面分析发现,氧化温度对合金中Nb添加元素的氧化行为影响较小,对V添加元素的氧化行为影响剧烈。两种合金元素对氧化过程有着显著的影响。