氮分压对反应溅射(Ti,Al)N薄膜微结构与力学性能的影响

采用Ti-Al复合靶在不同氮分压下制备了一系列(Ti,Al)N薄膜,用EDS、XRD、TEM和微力学探针表征了薄膜的沉积速率、化学成分、微结构和力学性能.结果表明,氮分压对(Ti,Al)N薄膜影响显著:合适的氮分压可以得到化学计量比的(Ti,Al)N薄膜,薄膜为单相组织,并呈现(111)择优取向,最高硬度和弹性模量分别达到34.4GPa和392GPa;过低的氮分压不但会造成薄膜贫氮,而且薄膜中的Al含量偏低,硬度不高;过高的氮分压下,由于存在"靶中毒"现象,尽管薄膜的成分无明显变化,但会大大降低其沉积速率,并使薄膜形成纳米晶或非晶态结构,薄膜的硬度也较低.     

反应溅射(Al,Ti)(O,N)涂层的微结构与力学性能

采用Al-Ti镶嵌复合靶在Ar、N2和O2混合气体中反应溅射制备了一系列(Al,Ti)(O,N)涂层.并采用EDS、XRD、TEM和微力学探针研究了薄膜的化学成分、微结构和力学性能.结果表明,随氧分压的提高,涂层中氧含量逐步增加,氮含量相应减少,(Al Ti):(O N)的化学计量比仍约为1:1,涂层保持与(Al,Ti)N涂层相同的NaCl结构.低氧含量时薄膜在(111)方向上择优生长,随着氧含量的提高,涂层生长的择优取向发生改变,高氧含量薄膜样品呈现强烈(200)织构的柱状晶.与此同时,(Al,Ti)(O,N)涂层的硬度和弹性模量也仍保持在与(Al,Ti)N涂层相当的35GPa和370～420GPa的高值.由于涂层中形成了相当含量的氧化物,这类涂层的抗氧化能力有望得到提高.     

射频磁控溅射制备(AlCrTiZrNb)N高熵合金薄膜的微观组织和力学性能

研究了氮含量对(Al Cr Ti Zr Nb)N高熵合金薄膜微观结构和力学性能的影响,利用射频磁控溅射工艺在不同N2和Ar流量比下制备了(Al Cr Ti Zr Nb)N高熵合金薄膜。结果表明,随着氮气流量的升高,(Al Cr Ti Zr Nb)N薄膜的沉积速率逐渐下降,Al Cr Ti Zr Nb合金薄膜的结构由非晶态转变为由Me-N(金属氮化物)构成的面心立方固溶体结构,(Al Cr Ti Zr Nb)N薄膜的择优生长取向为(200)晶面。同时随着N2流量的增加,(Al Cr Ti Zr Nb)N高熵合金薄膜的硬度首先快速升高,随后略微降低。当N2∶Ar=1∶1时,(Al Cr Ti Zr Nb)N薄膜硬度最大值28.324 GPa,此时(Al Cr Ti Zr Nb)N薄膜呈现单一的面心立方固溶体结构,饱和Me-N相的形成与各元素的固溶强化作用是其硬度的增长的主要原因。     

氮流量对采用独立钛靶制备的(Ti,Al)N薄膜结构与性能的影响

采用直流反应磁控溅射系统,选择独立Ti靶在3003AlMn合金表面在不同氮流量下制备(Ti,Al)N薄膜,采用扫描电镜、能谱分析、X射线衍射、极化曲线试验、磨损试验、薄膜厚度和显微硬度试验等手段表征了薄膜的沉积速率、化学成分、微结构和力学性能。结果表明,以独立Ti靶在铝衬底表面可以直接生成晶粒尺寸细小与基底结合良好的(Ti,Al)N薄膜,同时可以增加铝合金的表面硬度,提高表面耐蚀性能及表面光泽度。氮流量对(Ti,Al)N薄膜影响显著,氮流量为7cm3/min时制备的(Ti,Al)N薄膜晶粒最细小、致密,小尺寸纳米化的晶粒对提高3003AlMn合金耐磨损性和耐蚀性最佳,但沉积速率低,硬度增幅小。     

离子束辅助中频反应溅射 (Cr,Ti,Al)N薄膜的研究

为了提高工模具的服役性能,采用中频反应溅射,无灯丝离子源辅助的方法沉积了(Cr,Ti,Al)N多元硬质薄膜.分别用电子能谱、X-射线衍射、显微硬度计、划痕仪和干涉显微镜分析了薄膜的成分、相组成、硬度、膜/基结合力及膜层厚度.结果表明用此法制备的薄膜为含有多相结构的(Cr,Ti,Al)N多元硬质膜,晶粒细小,沉积速率快,显微硬度高达35 GPa,结合强度高度达80 N,综合性能优异.     

TiN,TiC和Ti(C,N)涂层的性能及影响因素研究

TiN和TiC同属于NaCl形式的晶体结构,是同构互溶性的.Ti(C,N)是两者的固溶体.TiN和TiC及Ti(C,N)涂层具有优良的力学和摩擦学性能,作为硬质耐磨涂层,已用于切削刀具、钻头和模具等场合,具有广泛的应用前景.综述了国内外关于这3种涂层的研究成果.研究了影响其性能的若干因素,比较了它们的性能差异,为进一步优化涂层的性能及合理地选用涂层提供了参考.进一步的研究方向是高、低温及恶劣环境下涂层的性能以及更大载荷下涂层的摩擦学性能等.一些重要结果如下:(1)对TiN涂层而言,用CAPD比用CAIP制备时,涂层的摩擦因数小、结合强度大、硬度小;脉冲电压从550 V增大到750 V时,涂层脆性增加、结合强度减小;在多弧离子镀工艺中,500 ℃是最佳沉积温度,此时涂层的硬度和结合强度均最大.(2)对用反应磁控溅射制备的TiC涂层而言,用C2H2比用CH4制备时,涂层的硬度大;CH4分压在0.02～0.04 Pa范围内为最佳,此时TiC涂层的硬度和弹性模量最大,分别是30.9 GPa和343.0 GPa.(3)对Ti(C,N)涂层而言,随CH4:N2或C2H2:N2流量比的增大,其硬度增大;CH4:N2分压比对摩擦因数和磨损量的影响还与载荷的大小有关;TiCxN1-x涂层的硬度和弹性模量随x值而变化,当x为0.6左右时,硬度取最大值45 GPa,当x值为0.43左右时,弹性模量取最大值630 GPa.     

反应溅射（Al，Ti）（0，N）涂层的微结构与力学性能

采用Al—Ti镶嵌复合靶在Ar、N2和O2混合气体中反应溅射制备了一系列（Al，Ti）（O，N）涂层。并采用EDS、XRD、TEM和微力学探针研究了薄膜的化学成分、微结构和力学性能。结果表明，随氧分压的提高，涂层中氧含量逐步增加，氮含量相应减少，（Al＋Ti）：（O＋N）的化学计量比仍约为1：1，涂层保持与（Al，Ti）N涂层相同的NaCl结构。低氧含量时薄膜在（111）方向上择优生长，随着氧含量的提高，涂层生长的择优取向发生改变，高氧含量薄膜样品呈现强烈（200）织构的柱状晶。与此同时，（Al，Ti）（O，N）涂层的硬度和弹性模量也仍保持在与（Al，Ti）N涂层相当的35GPa和370～420GPa的高值。由于涂层中形成了相当含量的氧化物，这类涂层的抗氧化能力有望得到提高。     

中间层类型对类金刚石涂层键合结构和性能的影响行为

采用阴极电弧离子镀和等离子体增强化学气相沉积(PECVD)相结合的技术方法,在304不锈钢基体上分别沉积制备了Ti/DLC和Ti/Ti N/Ti Al N/DLC复合涂层。选用原子力显微镜、拉曼光谱对涂层的形貌和结构进行表征测试。同时,利用显微硬度计、划痕测试仪系统地分析了涂层的显微硬度和界面结合性能,并研究了其摩擦磨损行为。研究结果表明:Ti/Ti N/Ti Al N/DLC复合涂层体系具有较高硬度(~2130HV)的同时结合性能最优(结合力~53.7 N),抗磨损能力最强。在相同试验条件下,无涂层的基体摩擦系数为0.45,单层DLC、Ti/DLC和Ti/Ti N/Ti Al N/DLC涂层的摩擦系数则分别为0.15、0.12和0.07。Ti/Ti N/Ti Al N/DLC复合涂层可有效提高304不锈钢的耐磨损性能,降低摩擦系数。     

磁控溅射CrNx薄膜的制备与力学性能

采用反应磁控溅射法在不同的氮分压下制备了一系列CrNx薄膜，并利用EDS和XRD表征了薄膜的成分和相组成，采用力学探针测量了薄膜的硬度和弹性模量。研究了氮分压对薄膜成分，相组成和力学性能的影响。结果表明，随氮分压的升高，薄膜的沉积速率明显降低，薄膜中的氮含量量增加，相应地，相组成从Cr Cr2N过渡到单相Cr2N,再逐步经Cr2N CrN过渡到单相CrN,并在Cr:N原子比为1：2和1：1时，薄膜的硬度出现极值（HV27．1GPa和HV26.8GPa),而薄膜的弹性模量则在Cr2N时呈现350GPa的最高值。     

溅射靶材对TiAlN涂层形貌、结构和力学性能的影响

采用粉末冶金和真空熔炼方法制备了原子比为Ti50Al50的合金靶材,利用磁控溅射工艺在同一工艺参数下制备了TiAlN涂层,借助扫描电镜、原子力显微镜、X射线衍射仪、纳米压痕和结合强度实验,研究了溅射靶材对TiAlN涂层的形貌、结构和力学性能的影响。结果表明:粉末靶材中Ti和Al以单质相存在,Ti镶嵌于Al基体周围,熔炼靶材中形成了TiAl和Ti3Al合金化片层组织;由于两种靶材在组织结构和导热性能上的不同导致其溅射产额、靶材温度和溅射金属离子能量等都出现了明显的差异;对涂层的影响表现为,相比于熔炼靶材涂层,粉末靶材涂层的沉积速率高44%,表面粗糙度低24%,涂层表面熔滴数目和尺寸较小;粉末靶材涂层呈现Ti2AlN相等轴晶生长方式,熔炼靶材涂层由于沉积温度较高表现为Ti2AlN相和TiN相,以等轴晶和柱状晶混合生长;相结构的不同导致涂层的硬度和结合强度出现差异,粉末靶材涂层硬度为25.69 GPa,结合强度属于HF-3,熔炼靶材涂层的硬度为28.22 GPa,结合强度属于HF-5。     

A study of the nanostructure and hardness of electron beam evaporated TiAlBN Coatings

TiAlBN coatings have been deposited by electron beam (EB) evaporation from a single TiAlBN material source onto AISI 316 stainless steel substrates at a temperature of 450 °C and substrate bias of − 100 V. The stoichiometry and nanostructure have been studied by X-ray photoelectron spectroscopy, X-ray diffraction and transmission electron microscopy. The hardness and elastic modulus were determined by nanoindentation. Five coatings have been deposited, three from hot-pressed TiAlBN material and two from hot isostatically pressed (HIPped) material. The coatings deposited from the hot-pressed material exhibited a nanocomposite nc-(Ti,Al)N/a-BN/a-(Ti,Al)B₂ structure, the relative phase fraction being consistent with that predicted by the equilibrium Ti-B-N phase diagram. Nanoindentation hardness values were in the range of 22 to 32 GPa. Using the HIPped material, coating (Ti,Al)B_0.29N_0.46 was found to have a phase composition of 72-79 mol.% nc-(Ti,Al)(N,B)_1 − x+ 21-28 mol.% amorphous titanium boride and a hardness of 32 GPa. The second coating, (Ti,Al)B_0.66N_0.25, was X-ray amorphous with a nitride+boride multiphase composition and a hardness of 26 GPa. The nanostructure and structure-property relationships of all coatings are discussed in detail. Comparisons are made between the single-EB coatings deposited in this work and previously deposited twin-EB coatings. Twin-EB deposition gives rise to lower adatom mobilities, leading to (111) (Ti,Al)N preferential orientation, smaller grain sizes, less dense coatings and lower hardnesses.     

Tribological Properties of Mo-N Hard Coatings on Ti6Al4V by Double Glow Discharge Technique

Mo-N hard coatings on Ti6Al4V were formed using double glow discharge technique. The fundamental coating properties, such as the phase, hardness and elastic modulus were investigated. The tribological performances of the coatings in dry wear condition were studied by means of ball-on-disc wear machine. The experimental results showed that the thickness of the Mo-N hard coating was about 10 µm. The coating was single fcc γ-Mo2N phase with (200) preferred orientation. The hardness and the elastic modulus of the coating was 13.80 GPa and 261.65 GPa respectively. The surface treatment enhanced the hardness and elastic modulus of the surface of Ti6Al4V base greatly. With GCr15 slider ball, the friction coefficient of the Mo-N hard coating was in the range of 0.56~0.65 at the steady state. Though the coating did not show friction reducing effect, it improved the wear resistance of Ti6Al4V greatly.     

磁控双靶反应共溅射(Ti,Al)N薄膜的研究

采用磁控双靶反应共溅射技术制备出了(Ti0.5Al0.5)N耐磨硬质薄膜,其显微硬度高于35GPa,摩擦系数小于0.18.实验结果表明当N2流量较低时,(Ti,Al)N薄膜结构和性能随N2流量变化明显;当N2流量较高时,薄膜结构和性能变化缓慢.等离子体发射光谱仪(PEM)对磁控反应溅射过程监测结果表明,钛铝原子与氮原子反应存在一个临界点,低于临界点,磁控反应溅射为金属态溅射模式,高于临界点,磁控溅射向非金属态溅射模式转变,溅射速率降低.     

Influence of N2 partial pressure on mechanical properties of (Ti,Al)N films deposited by reactive magnetron sputtering

The influence of the nitrogen partial pressure on the mechanical properties of (Ti,Al)N films deposited by DC reactive magnetron sputtering using a Ti-Al mosaic target at a substrate bias of −100 V is investigated. Nanoindentation tests reveal that with increasing N₂ partial pressure, the film hardness and elastic modulus increase initially and then decrease afterwards. The maximum hardness and elastic modulus are 43.4 GPa and 430.8 GPa, respectively. The trend is believed to stem from the variations in the grain size and preferential orientation of the crystals in the (Ti,Al)N films fabricated at varying N₂ partial pressure. The phenomenon is confirmed by results acquired using glancing angle X-ray diffraction (XRD) and energy dispersive X-ray spectroscopy (EDS).     

Effect of Nitrogen Content on Microstructures and Mechanical Properties of WB_2(N) Films Deposited by Reactive Magnetron Sputtering

In the present study,WB_2(N) films are fabricated on silicon and YG8 substrates at different N_2 pressures by reactive magnetron sputtering.The influence of N_2 partial pressure(P_(N2)) on the film microstructure and characteristics is studied systematically,including the chemical composition,crystalline structure,residual stress,surface roughness as well as the surface and the cross-section morphology.Meanwhile,nano-indentation and ball-on-disk tribometer are performed to analyze the mechanical and tribological properties of the films.The results show that the addition of nitrogen apparently leads to the change of the structure from(1 0 1) to(0 0 1) orientation then to the amorphous structure with the formation of BN phase.And the addition of nitrogen can greatly refine the grain size and microstructure of the films.Furthermore,the residual stress of the film is also found to change from tensile to compressive stress as a function of P_(N2),and the compressive stress increases with P_(N2),The WB_2(N) films with small nitrogen content,which are deposited at P_(N2) of 0.004 and 0.006 Pa,exhibit better mechanical,tribological and corrosion properties than those of other films.Further increase of nitrogen content accelerates the formation of BN phase and fast decreases the film hardness.In addition,the large N_2 partial pressure gives rise to the target poisoning accompanied by the increase of the target voltage and the decrease of the deposition rate.     

Influence of boron doping on mechanical and tribological properties in multilayer CVD-diamond coating systems

Titanium alloy (Ti6Al4V) substrates were deposited with smooth multilayer coatings, by hot filament chemical vapour deposition technique. The effect of boron doping on lattice parameter, residual stresses, hardness and coefficient of friction in multilayer-diamond coating system was studied. The frictional behaviour of the coatings was studied using a ball-on-disc micro-tribometer by sliding the coated samples of titanium alloy (Ti6Al4V) substrates against alumina (Al₂O₃) balls, and increasing normal load from 1 to 10 N. The average friction coefficient decreased from 0.36 to 0.29 for undoped multilayer-diamond coating system and from 0.33 to 0.18 for boron- doped (BD) multilayer-diamond coating system. The average indentation depths for undoped and BD multilayer- diamond coating systems were found to be equal to ～>58 and ～65 nm, respectively, and their hardness values were 60 and 55 GPa, respectively.     

钛合金表面非平衡磁控溅射制备氮化钛薄膜性能研究

本文利用非平衡磁控溅射技术，通过改变薄膜沉积时氮气和氩气分压比（PN／PAr）和靶基距，在Si（100）和钛合金（Ti6A14V）基体上制备了氮化钛薄膜。利用X射线衍射（XRD）、扫描电子显微镜（SEM）、HXD-1000显微硬度仪和（CSEM）销盘摩擦磨损实验机对氮化钛薄膜的晶体结构、断面形貌、显微硬度和耐磨性进行了表征。研究发现，利用非平衡磁控溅射制备出致密的氮化钛薄膜，PN／PAr较小时，氮化钛薄膜中存在Ti2N相，Ti2N能够提高薄膜的硬度与耐磨性，随着N2／Ar的提高，薄膜硬度、耐磨性提高，当PN／PAr达到0．1时，随着N2／Ar的提高，薄膜硬度、耐磨性降低。结果表明，在钛合金表面制备氮化钛薄膜可以显著提高钛合金表面硬度与耐磨性，在改善用于人工心脏瓣膜的力学性能，提高人工心脏瓣膜的瓣架耐磨性，提高人工心脏瓣膜的寿命方面有较广阔的应用前景。     

Deposition of a nanocomposite (Ti,Al, Si)N coating with high thickness by high-speed physical vapor deposition

Nanocomposite coatings such as (Ti, Al, Si)N have been demonstrated as promising candidates for the use as protection against solid particle erosion for compressor blades. Typically, nanocomposite (Ti, Al, Si)N coatings are deposited by different physical vapor deposition (PVD) techniques. However, the relatively low coating thickness up to a few micrometers due to low deposition rates leads to a limited lifetime of the coatings under erosive particle bombardment. In this study, the deposition of a nanocomposite (Ti, Al, Si)N coating was performed by a hollow cathode gas flow sputtering method, the high-speed physical vapor deposition, which enables the high-rate deposition of thick coatings. Morphology and microstructure of the coating were investigated via scanning electron microscopy and transmission electron microscopy, respectively. Tribological characterization by impact tests and erosion tests demonstrates that the nanocomposite (Ti, Al, Si)N coated sample reveals a promising resistance against impact loads and the solid particle erosion. Summarily, nanocomposite (Ti, Al, Si)N coatings deposited by the high-speed physical vapor deposition provide a high potential for the erosion protection of compressor blades.