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.     

c-AIN的生长对AIN/(Ti,Al)N纳米多层膜力学性能的影响

采用反应磁控溅射制备了具有不同调制周期的AIN/(Ti,Al)N纳米多层膜,研究了亚稳相立方氮化铝(c-AIN)在纳米多层膜中的生长条件及其对薄膜力学性能的影响。结果表明:在小调制周期下AIN以立方结构存在,并与(Ti,Al)N层形成同结构共格外延生长,使纳米多层膜产生较大的晶格畸变。与此相应,AIN/(Ti,Al)N纳米多层膜硬度和弹性模量随调制周期的减小呈单凋上升的趋势,当调制周期小于8～10 nm时其增速明显增大,并在调制周期为1.3 nm时达到最高硬度29.0GPa和最高弹性模量383 GPa.AIN/(Ti,Al)N纳米多层膜的硬度和弹性模量在小调制周期时的升高与亚稳相c-AIN的产生并和(Ti,Al)N形成共格结构有关。     

磁控溅射制备AlTiCrNiTa/(AlTiCrNiTa)N多层涂层的力学性能及微结构分析

利用反应磁控溅射N₂流量灵活可调的特点，在Zr-4基底上，制备了由AlTiCrNiTa高熵合金和(AlTiCrNiTa)N高熵合金氮化物交替调制的多层结构涂层。利用场发射扫描电镜(SEM)、X射线衍射(XRD)、自动划痕法(Automatic Scratch)和纳米压痕(Nanoindentation)等表征与测试手段，对调制周期为2、4、8和20的多层涂层微观形貌、晶体结构、纳米硬度和结合力进行了分析。实验结果表明，多层涂层由非晶态的AlTiCrNiTa和FCC的(AlTiCrNiTa)N组成，涂层纳米硬度随层数增加而先降后升，调制周期为20时达到52.31 GPa。此外，所有多层涂层与基底的结合强度均大于100 N。     

结构调制超硬Ti/TiN纳米多层膜的制备及其尺寸效应

使用多弧离子镀技术在高速钢基体上制备了调制周期为5~40 nm的Ti/TiN纳米多层膜,用扫描电子显微镜(SEM)、X射线能谱仪(EDS)、X射线衍射仪(XRD)、纳米压痕仪和划痕仪等手段表征薄膜的微观结构和性能,研究了调制周期对Ti/TiN纳米多层膜性能的影响,并讨论了在小调制周期条件下Ti/TiN纳米多层膜的超硬效应和多弧离子镀技术对纳米多层膜硬度的强化作用。结果表明,与单层TiN相比,本文制备的Ti/TiN纳米多层膜分层情况良好,薄膜均匀致密,没有明显的柱状晶结构,TiN以面心立方结构沿(111)方向择优生长。随着调制周期的减小薄膜的硬度呈现先增大后减小的趋势,并在调制周期为7.5 nm时具有最大的硬度42.9 GPa和H/E值。这表明,Ti/TiN在具有最大硬度的同时仍然具有良好的耐磨性和韧性。Ti/TiN纳米多层膜的附着力均比单层TiN薄膜的附着力高,调制周期为7.5 nm时多层膜的附着力为(58±0.9) N。     

具有纳米调制结构的AlTiN/AlCrN复合涂层在干摩擦条件下的摩擦磨损性能研究

目的 研究干摩擦条件下不同AlTiN/AlCrN多层膜纳米调制结构对摩擦磨损行为的影响。方法 将处理过的合金工具钢和单晶硅片作为膜层生长的基底材料,在膜层制备之前,先对基底材料进行预处理,然后使用多靶磁控溅射纳米膜层系统沉积一系列不同调制周期和调制比的AlTiN/AlCrN纳米多层膜。通过控制涂层总厚度不变,在调制比为1︰1时,设计不同的调制周期,择优选出磨损量最小、耐磨性最好的调制周期,并以此为恒定值,进而设计不同调制比的试样。采用X射线衍射仪(XRD)、摩擦磨损试验机分析与表征纳米多层膜的微观结构和性能,研究调制周期和调制比对AlTiN/AlCrN纳米多层膜微观结构和干摩擦条件下摩擦磨损性能的影响。结果 AlTiN/AlCrN纳米多层膜主体均为面心立方结构,且在(111)、(200)和(220)晶面择优取向。调制结构对多层膜的磨损特性影响较大,当调制周期为14.4 nm时,在干摩擦条件下AlTiN/AlCrN纳米多层膜的摩擦磨损量最小;在调制周期恒定为14.4 nm情况下,当调制比为3︰1时,在干摩擦条件下AlTiN/AlCrN纳米多层膜的耐磨性能最好;AlTiN/AlCrN纳米多层膜的磨损机理主要以磨粒磨损和黏附磨损为主。结论 优化的AlTiN/AlCrN多层膜纳米调制结构技术可应用在切削刀具的表面再制造领域,从而延长刀具工作寿命,通过涂层良好的耐磨性能提升设备的加工效率。     

HfN/HfB_2纳米多层膜结构调制及其力学性能

为了进一步了解调制周期对HfN/HfB2纳米多层膜力学性能的影响,利用多靶磁控溅射技术,在Si(100)基底上制备了一系列具有相同厚度不同调制周期的HfN/HfB2纳米多层膜。利用XRD、TEM、XP-2台阶仪、纳米压痕仪及摩擦试验机分别分析了多层膜的结构特征、力学性能和室温下摩擦性能。结果表明,室温下沉积的多层膜呈现出结晶/非晶的混合结构;随着调制周期的增大,多层膜的结晶程度先增加后降低,其硬度和弹性模量也呈现出先升高后降低的趋势;当调制周期为40nm时,多层膜的硬度和弹性模量均达到最大值,分别为(36.72±1.3)和(378.41±5.6)GPa,并且此时多层膜具有较高的膜基结合力(Lmax=67.3mN)和较低的平均摩擦系数(0.061);在调制周期为20nm时,多层膜的残余应力达到最小值为-0.82GPa;经过高温退火后,多层膜的硬度和弹性模量均无明显变化,说明其具有良好的热稳定性;多层膜的结构和力学性能随调制周期的变化归因于晶粒的细化。     

c-AlN的生长对AlN/(Ti,Al)N纳米多层膜力学性能的影响

采用反应磁控溅射制备了具有不同调制周期的AlN／(Ti，Al)N纳米多层膜，研究了亚稳相立方氮化铝(c—AlN)在纳米多层膜中的生长条件及其对薄膜力学性能的影响．结果表明：在小调制周期下AlN以立方结构存在，并与(Ti，Al)N层形成同结构共格外延生长，使纳米多层膜产生较大的品格暗变．与此相应，AlN／(Ti，Al)N纳米多层膜硬度和弹性模量随调制周期的减小呈单调上升的趋势，当调制周期小于8～10nm时其增速明显增大，并在调制周期为1．3nm时达到最高硬度29．0GPa和最高弹性模量383GPa,AlN／(Ti，Al)N纳米多层膜的硬度和弹性模量在小调制周期时的升高与亚稳相c—AlN的产生并和(Ti，Al)N形成共格结构有关。     

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。     

调制周期对TiB_2/TiAlN纳米多层膜机械性能的影响

利用射频磁控溅射技术,在室温下合成了具有纳米调制周期的TiB2/TiAlN多层膜.分别采用表面轮廓仪、纳米力学测试系统、多功能材料表面性能实验仪和XRD,分析了调制周期对TiB2/TiAlN纳米多层膜机械性能的影响.结果表明大部分多层膜的纳米硬度和弹性模量值都高于两种个体材料混合相的值,在调制周期为25 nm时,多层膜体系的硬度超过了36GPa,性能达到较佳效果.     

ZrC/ZrB2纳米多层膜的微观结构与机械性能的研究

选择ZrC和ZrB2为个体层材料,利用射频磁控溅射系统在室温下制备具有纳米尺寸的ZrC/ZrB2多层膜.通过X射线衍射仪、扫描电子显微镜、俄歇电子能谱、表面轮廓仪及纳米力学测试系统研究了调制周期与ZrC,ZrB2单层厚度比例(tZrCtZrB2)对多层膜生长结构和力学性能的影响.结果表明,多层膜的界面清晰,调制周期性好,大部分多层膜的纳米硬度和弹性模量值都高于两种个体材混合相的值,在调制比例tZrCtZrB2=11.7、调制周期为32 nm时,薄膜显示出很强的ZrC(111)择优趋向和较弱的ZrB2(001)及ZrB2(002)结构,同时产生硬度异常升高的超硬效应,其硬度达到42 GPa.多层膜的机械性能改善明显与其调制结构和多晶结构有着直接的联系.     

TiN/VCN多层膜的力学性能及摩擦磨损性能研究

采用多靶磁控溅射技术, 制备了TiN、VCN单层膜及调制比为1:1的系列调制周期的TiN/VCN多层膜。利用X射线衍射仪、纳米压痕仪、高温摩擦磨损测试仪和扫描电子显微镜研究了各种薄膜的微结构、力学性能及室温和高温摩擦磨损性能。研究表明: TiN/VCN多层膜以δ-NaCl面心立方结构为主; TiN/VCN多层膜的最大硬度值为28.71 GPa, 约为按混合法则计算所得理论硬度值的1.23倍, 并据此分析了TiN/VCN多层膜的致硬机理; TiN/VCN多层膜在室温下摩擦系数与TiN单层膜摩擦系数相近, 但当环境温度为700℃时, 摩擦系数约0.4, 较TiN单层膜(0.52)低。TiN/VCN多层膜室温和高温下的磨损率相比TiN单层膜减小了约3×10^-14 m³/(N·m)。从晶体化学和热测量方法角度讨论了TiN/VCN多层膜的Magnéli相V₂O₅的润滑机制。     

Coherent growth and superhardness effect of AlN/TiN nanomultilayers

The formation of metastable cubic AlN (c-AlN) and its effect on the mechanical properties of AlN/TiN nanomultilayers were studied. A series of AlN/TiN multilayers with different modulation periods were prepared by reactive magnetron sputtering. The microstructure and mechanical properties of multilayers were characterized with low-angle X-ray diffraction, transmission electron microscopy and a microhardness tester. The results show that AlN exists as a metastable cubic phase in multilayers at small modulation periods due to the “template effect” of TiN layer and forms superlattice with TiN through coherent epitaxial growth. Correspondingly, multilayers show the superhardness effect with the enhancement of hardness at small modulation periods. With the increase of modulation periods, AlN layer grows as c-AlN firstly and then its stable hexagonal structure (h-AlN) appears and grows on the already formed c-AlN. Correspondingly, the hardnesses of the multilayers decrease. The change of properties with the formation of c-AlN and the alternative strain field resulting from coherent growth of c-AlN and TiN are likely reasons for the superhardness effect of AlN/TiN multilayers.     

Corrosion behavior of nanolayered TiN/NbN multilayer coatings prepared by reactive direct current magnetron sputtering process

TiN, NbN and TiN/NbN multilayer coatings were deposited on tool steel substrates using a reactive DC magnetron sputtering process. The coatings were characterized using X-ray diffraction, nanoindentation, atomic force microscopy, scanning electron microscopy (SEM) and energy-dispersive X-ray analysis. The corrosion behavior of TiN/NbN multilayer coatings was studied in 0.5 M HCl and 0.5 M NaCl solutions using potentiodynamic polarization and compared with single layered TiN and NbN coatings. Approximately 1.5 μm thick coatings of TiN, NbN and TiN/NbN multilayers showed good corrosion protection of the tool steel substrate and multilayer coatings performed better than single layered coatings. The corrosion behavior of the multilayers improved with total number of interfaces in the coatings. In order to conclusively demonstrate the positive effect of layering, corrosion behavior of 40-layer TiN/NbN multilayers was studied at lower coating thicknesses (32–200 nm) and compared with single layer TiN coatings of similar thicknesses. The polarization data and SEM studies of these coatings indicated that the corrosion behavior improved with coating thickness and multilayers showed better corrosion resistance as compared to the single layer coatings. Other studies such as intrinsic corrosion, effects of Ti interlayer and post-deposition annealing on the corrosion behavior of the multilayer coatings are also presented in this paper. The results of this study demonstrate that nanolayered multilayers can effectively improve the corrosion behavior of transition metal nitride hard coatings.     

Structure, hardness and thermal stability of nanolayered TiN/CrN multilayer coatings

Nanolayered TiN/CrN multilayer coatings were deposited on silicon substrates using a reactive DC magnetron sputtering process at various modulation wavelengths (Λ), substrate biases (V_B) and substrate temperatures (T_S). X-ray diffraction (XRD), nanoindentation and atomic force microscopy (AFM) were used to characterize the coatings. The XRD confirmed the formation of superlattice structure at low modulation wavelengths. The maximum hardness of the TiN/CrN multilayers was 3800 kg/mm² at Λ=80  Å, V_B=−150 V and T_S=400°C. Thermal stability of TiN, CrN and TiN/CrN multilayer coatings was studied by heating the coatings in air in the temperature range (T_A) of 400-800°C. The XRD data revealed that TiN/CrN multilayers retained superlattice structure even up to 700°C and oxides were detected only after T_A?750°C, whereas for single layer TiN and CrN coatings oxides were detected even at 550°C and 600°C, respectively. Nanoindentation measurements showed that TiN/CrN multilayers retained a hardness of 2800 kg/mm² upon annealing at 700°C, and this decrease in the hardness was attributed to interdiffusion at the interfaces.     

Microstructure and hardening mechanisms in a-Si3N4/nc-TiN nanostructured multilayers

Amorphous/nanocrystalline Si₃N₄/TiN nanostructured multilayer films were fabricated by radio-frequency reactive magnetron sputtering. The microstructure and properties of these films were measured using an X-ray diffractometer, X-ray photoelectron spectroscope, high-resolution transmission electron microscopy and nanoindenter. The superhardness effect was found in Si₃N₄/TiN multilayers. The hardness of Si₃N₄/TiN multilayers is affected not only by modulation periods, but also by layer thickness ratio and deposition temperature. The hardness value is about 40% higher than the value calculated from the rule of mixtures at a deposition temperature of 500 °C and a layer thickness ratio (l_Si3N4/l_TiN) of 3/1. The hardening mechanisms in this system are discussed in the light of our experimental results. Results of calculation of the theoretical stress distribution in the multilayers suggests that alternating stress fields caused by thermal mismatching between Si₃N₄ and TiN is one of the main reasons for the superhardness effect observed in Si₃N₄/TiN multilayers.     

Epitaxial growth of MgO/TiN multilayers on Cu

The growth of epitaxial MgO/TiN multilayer films on (001) Cu has been investigated. In particular, epitaxial structures were grown on (001) Cu layers that were epitaxial on (001) SrTiO₃. X-ray diffraction and reflection high-energy electron diffraction indicate that the multilayer structures are epitaxial on the (001) Cu surface. The motivation is the use of crystalline MgO/TiN multilayers as a diffusion barrier to both copper and oxygen. MgO/TiN multilayers are potentially useful as diffusion barriers for Cu interconnects on semiconductors as well as for superconducting wires based on the epitaxial growth of cuprate superconductors on biaxially textured copper.     

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。     

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.     

Influence of substrate temperature on the materials properties of reactive DC magnetron sputtered Ti/TiN multilayered thin films

Ti/TiN multilayers were deposited by DC reactive magnetron sputtering method using a titanium target and an Ar-N₂ mixture discharge gas. XRD technique was employed to study the structure of the coatings and to observe the variations of structural parameters with substrate temperatures. An increase in grain size with increase of substrate temperature was observed. The components of Ti 2p doublet, related to TiN, TiON and TiO₂, were observed in the core-level spectra of the deposited multilayer films from XPS analysis. A microhardness value of 25.5 GPa was observed for Ti/TiN multilayers prepared at 400 °C. Electrical properties were found to depend on substrate temperature.