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1.
采用多弧离子镀技术和Ti-Al合金靶及Zr单质靶的组合,在高速钢基体上制备了(Ti,Al,Zr)N多元N梯度硬质反应膜.分别用扫描电镜、X射线衍射仪观察测定(Ti,Al,Zr)N梯度膜膜层的表面、断面形貌、成分以及相结构,研究了(Ti,Al,Zr)N多元氮梯度硬质反应膜的组织结构和性能.结果表明,与TiN、(Ti,Al...  相似文献   

2.
采用直流反应磁控溅射工艺,在载波片和Al基材上制备出金黄色的(Ti,Zr)N薄膜.(Ti,Zr)N薄膜具有比TiN薄膜更高的硬度和更强的耐腐蚀性能.用XRD衍射方法和扫描隧道显微镜对薄膜的晶体结构、微观表面形貌和电子结构进行了测试分析.XRD结果表明,(Ti,Zr)N薄膜为多晶态,存在TiN和ZrN两种分离相;从表面形貌可知,薄膜表面平整,晶粒排列致密且无连接松散的大颗粒;STS谱表明,Zr掺杂后,禁带宽度仍为1.64eV,但在禁带内增加了新能级,新能级的宽度分别为0.33eV和0.42eV,这也正是掺杂Zr后,薄膜仍呈现金黄色的主要原因.  相似文献   

3.
Electromagnetic wave (EMW) absorbing materials play a vital role in modern communication and information processing technologies to inhibit information leakage and prevent possible damages to environment and human bodies.Currently,most of EMW absorbing materials are either composites of two or more phases or in the form of nanosheets,nanowires or nanofibers in order to enhance the EMW absorption performance through dielectric loss,magnetic loss and dielectric/magnetic loss coupling.However,the combination of complex shapes/multi phases and nanosizes may compound the difficulties of materials processing,composition and interfaces control as well as performance maintenance during service.Thus,searching for single phase materials with good stability and superior EMW absorbing properties is appealing.To achieve this goal,the EMW absorbing properties of transition metal carbides TMCs (TM=Ti,Zr,Hf,Nb and Ta) and high entropy (Ti0.2Zr0.2Hf0.2Nb0.2Ta0.2)C which belong to ultrahigh temperature ceramics,were investigated in this work.Due to the good electrical conductivity and splitting ofd orbitals into lower energy t2g level and higher energy eg level in TMC6 octahedral arrangement,TMCs (TM=Ti,Zr,Hf,Nb and Ta) exhibit good EMW absorbing properties.Especially,HfC and TaC exhibit superior EMW absorbing properties.The minimum reflection loss (RLmin) value of HfC is -55.8 dB at 6.0 GHz with the thickness of 3.8 mm and the effective absorption bandwidth (EAB) is 6.0 GHz from 12.0 to 18.0 GHz at thickness of 1.9 mm;the RLmin value of TaC reaches-41.1 dB at 16.2 GHz with a thickness of 2.0 mm and the EAB is 6.1 GHz with a thickness of 2.2 mm.Intriguingly,the electromagnetic parameters,i.e.,complex permittivity and permeability are tunable by forming single phase solid solution or high entropy (Ti0.2Zr0.2Hf0.2Nb0.2Ta0.2)C.The RLmin value of high entropy (Ti0.2Zr0.2Hf0.2Nb0.2Ta0.2)C is -38.5 dB at 9.5 GHz with the thickness of 1.9 mm,and the EAB is 2.3 GHz (from 11.3 to 13.6 GHz) atthickness of 1.5 mm.The significance of this work is that it opens a new window to design single phase high performance EMW absorbing materials by dielectric/magnetic loss coupling through tuning the conductivity and crystal field splitting energy of d orbitals of transition metals in carbides,nitrides and possibly borides.  相似文献   

4.
Zr/ZrCN multilayers, with bilayer periods ranging from 4.4 to 70 nm, were deposited on C45 and M2 steels and Si substrates by the cathodic arc technique, in a CH4 + N2 atmosphere. The elemental and phase composition, modulation periodicity, texture, surface morphology, residual stress, hardness, adhesion, friction and wear behavior were investigated as a function of bilayer period and C/N ratio using AES, RBS, XRR, XRD and AFM techniques, surface profilometry, Vickers microhardness and scratch adhesion measurements, and tribological tests. Two types of Zr/ZrCN multilayers, with high and low C/(C + N) ratios (0.7 and 0.2, respectively) in the ZrCN sub-layer composition, have been prepared. The investigations indicated that the microchemical, microstructural, mechanical and tribological characteristics of the multilayered coatings depended on C/N ratio and bilayer period. For the optimum structure parameters (bilayer periods in the range 6–13 nm), the tribological performance of the multilayers was found to be superior to that of the ZrCN monolayers.  相似文献   

5.
许多年来,氮化钛镀膜的使用相当普遍。在周期表中与钛属于同一周期的另一过渡元素锆,亦是一引人注目的材料。已有许多关于氮化锆的研究,然而,对碳氮化锆的了解仍然有限。本研究使用非平衡磁控溅镀系统制备了ZrCN镀膜,探讨了C2H2/N2反应气体流量比例、以及添加Ti、W等对ZrCN硬度和磨耗性能的影响。结果显示,在总反应气体流量固定不变状态下,ZrCN硬度及磨润性能随反应气体流量比例降低而增加;添加Ti和W会显著增加ZrCN的硬度和磨耗性能,添加Ti的效果比添加W的佳。不论有无添加物,Zr CN的磨耗性能皆明显比TiN的佳。  相似文献   

6.
(Cr,Ti,Al,Zr)N梯度膜性能优异。采用多弧离子镀技术,使用Ti-Al-Zr合金靶和Cr单质靶在高速钢表面制备(Cr,Ti,Al,Zr)N多元超硬梯度膜,利用扫描电镜、能谱、X射线衍射仪、硬度计、划痕仪对膜层形貌、成分、结构、硬度、附着力进行分析,并通过热震性能试验考察了膜层的抗热震性能。结果表明:制备的膜层为面心立方结构,择优生长取向为(220)面;与TiN,(Ti,Al)N,(Ti,Cr)N,(Ti,Al,Zr)N等硬质膜相比,制备的(Cr,Ti,Al,Zr)N多元梯度膜具有更高的硬度和膜/基附着力,硬度可达4400HV,膜/基附着力大于200N,实现了从硬质膜到超硬膜的转变;膜层中N含量梯度可有效减少应力集中,Cr,Al含量的增加有利于提高膜层抗热震性能;负偏压对膜层硬度影响较大,对膜层成分、结构、抗热震性能影响较小,对膜/基附着力基本无影响。  相似文献   

7.
With the continued downscaling of complementary metal-oxide-semiconductor field effect transistor dimensions, high-dielectric constant (high-k) gate materials, as alternatives to SiO2, have been extensively investigated. Hf (Zr)-based high-k gate dielectric thin films have been regarded as the most promising candidates for high-k gate dielectric according to the International Technology Roadmap for Semiconductor due to their excellent physical properties and performance. This paper reviews the recent progress on Hf (Zr)-based high-k gate dielectrics based on PVD (physical vapor deposition) process. This article begins with a survey of various methods developed for generating Hf (Zr)-based high-k gate dielectrics, and then mainly focuses on microstructure, synthesis, characterization, formation mechanisms of interfacial layer, and optical properties of Hf (Zr)-based high-k gate dielectrics. Finally, this review concludes with personal perspectives towards future research on Hf (Zr)-based high-k gate dielectrics.  相似文献   

8.
采用射频磁控反应溅射在单晶Si(100)上沉积了一系列不同Al含量的(Zr,Al)N薄膜,利用能谱仪(EDS)、X射线衍射仪(XRD)、扫描电镜(SEM)和微力学探针对薄膜的成分、结构、力学和抗氧化性能进行了表征。研究结果表明,当Al含量在0%~20.31%(原子分数)之间时,薄膜是B1型(NaCl)单相结构;当Al含量为31.82%时,同时出现B1和B4型(ZnS)双相结构。当Al含量超过36.82%时,以B4结构为主。随着铝含量的增加,薄膜晶面间距减小,晶格常数变小。薄膜的力学性能测试表明,适当的Al含量可以提高薄膜的硬度。随着Al含量的增加,薄膜的抗氧化性能得到改善,对于B1型(Zr,Al)N薄膜,其结构稳定性也得到增强。  相似文献   

9.
High entropy diborides are new categories of ultra-high temperature ceramics,which are believed promising candidates for applications in hypersonic vehicles.However,knowledge on high temperature thermal and mechanical properties of high entropy diborides is still lacking unit now.In this work,variations of thermal and elastic properties of high entropy (Ti0.2Zr0.2Hf0.2Nb0.2Ta0.2)B2 with respect to temperature were predicted by molecular dynamics simulations.Firstly,a deep learning potential for Ti-Zr-Hf-Nb-Ta-B diboride system was fitted with its prediction error in energy and force respectively being 9.2 meV/atom and 208 meV/(A),in comparison with first-principles calculations.Then,temperature dependent lattice constants,anisotropic thermal expansions,anisotropic phonon thermal conductivities,and elastic properties of high entropy (Ti0.2Zr0.2Hf0.2Nb0.2Ta0.2)B2 from 0 ℃ to 2400 ℃ were evaluated,where the predicted room temperature values agree well with experimental measurements.In addition,intrinsic lattice distortions of (Ti0.2Zr0.2Hf0.2Nb0.2Ta0.2)B2 were analyzed by displacements of atoms from their ideal positions,which are in an order of 10-3 (A) and one order of magnitude smaller than those in (Ti0.2Zr0.2Hf0.2Nb0.2Ta0.2)C.It indicates that lattice distortions in (Ti0.2Zr0.2Hf0.2Nb0.2Ta0.2)B2 is not so severe as expected.With the new paradigm of machine learning potential,deep insight into high entropy materials can be achieved in the future,since the chemical and structural complexly in high entropy materials can be well handled by machine learning potential.  相似文献   

10.
The effect of nitrogen flow rate on structure and properties of (Ti,Zr)N thin films was investigated in the study. Two types of (Ti,Zr)N thin films were found with different nitrogen flow rates, one is the single-phase solid solution of (Ti,Zr)N that appeared for nitrogen flow rates of 2-7 sccm, the other one is the phase of both (Ti,Zr)N and TiZr mixture for the lower nitrogen flow rates of 1 sccm. The grain size of the films was also determined by X-ray diffraction, and the size was less than 20 nm. The (Ti,Zr)N films show excellent hardness ranging from 35.5 to 37.5 GPa with exhibiting (111) preferred orientation.  相似文献   

11.
用射频反应磁控溅射方法制备了MeNx(Me=Ti、Zr、Hf)薄膜,研究了在富N2条件下不同的N2/Ar流量比对薄膜结构和光学性能的影响.掠角X射线衍射的分析结果表明,所制得的富氮的TiNx薄膜主要由TiN所组成,而富氮的ZrNx、HfNx薄膜则具有非晶态的结构.用分光光度计和傅里叶红外仪对薄膜的光学透过率的测试表明,...  相似文献   

12.
采用多弧离子镀技术制备了不同金属组元配比的(ZrTiAl) N硬质反应膜,进而考查金属组元配比对(ZrTiAl) N硬质反应膜的相组成和硬度的影响规律。为保证(ZrTiAl) N膜层中Zr、Ti、Al组元含量配比的规律性变化,对膜层沉积过程中弧源靶及电流分别进行了设定。通过扫描电镜进行(ZrTiAl) N膜层表面形貌和断面形貌观察及成分测定。X射线小角度衍射方法用于膜层相结构测试分析。采用VICKERS 402 MVD硬度仪测定膜层的表面硬度。所制备的(ZrTiAl) N膜层保持了膜层表面形貌、断面形貌以及膜层厚度的一致性。(ZrTiAl) N膜层均为单一固溶体型(ZrTiAl) N面心立方相组成,具有单一的(111)面择优生长取向,其点阵常数随金属组元配比的变化基本符合Vegard定律。在金属组元配比的较大变化范围内,(ZrTi Al) N膜层的相组成和择优生长取向未改变,均具有较高的硬度。在以Zr N为基的(ZrTiAl) N膜层中,Ti N和Al N的含量较大并且接近相等时,膜层容易达到硬度极大值。  相似文献   

13.
制备了复合添加0.8%(原子分数)Nb+0.9%(原子分数)Zr和复合添加1.5%(原子分数)Nb+1.2%(原子分数)Zr的两种粉末烧结Nd(Dy,Gd)Fe(Nb,Zr,Al,Cu)B永磁体,通过对它们的微观结构、微区成分以及磁性能的分析,研究了Nb、Zr添加量对磁体晶界相形成的影响以及晶界新相与磁体矫顽力之间的关...  相似文献   

14.
采用射频磁控溅射装置在氩气氛下制备了Fe(Co)Al(Zr)O系薄膜.用X射线衍射仪、透射电镜及其选区衍射来分析薄膜的微结构.用振动样品磁强计、磁导计等测量了矫顽力Hc、饱和磁化强度Ms及磁导率等磁性参数.通过退火处理研究了Fe(Co)Al(Zr)O系薄膜的磁性能.Fe(Co)Al(Zr)O系薄膜磁各向异性是由形状各向异性引起的.  相似文献   

15.
Ferroelectric/antiferroelectric bi-layer ceramics with different ferroelectric and antiferroelectric phase thickness ratio (FE/AFE thickness ratio) in Pb(Nb, Zr, Sn, Ti)O3 system were prepared and characterized. With increasing the maximum external electric field from 0 to 40 kV/cm, polarization-electric field relation was always ferroelectric-like or underwent an antiferroelectric-ferroelectric transition, depending on the FE/AFE thickness ratio. All layered ceramics showed ferroelectric-like hysteresis loops with maximum external electric field of 40 kV/cm, and much higher remanent polarizations were attained than those of the ferroelectric/antiferroelectric heterostructures reported previously.  相似文献   

16.
通过直流磁控溅射法在单晶Si(100)基底上制备了Zr/Nb/Si薄膜材料。X射线衍射(XRD)研究表明Zr薄膜以多晶形式存在,而Nb薄膜则形成了(110)晶面择优生长。薄膜中Zr和Nb晶粒大小分别为14,6 nm。扫描电镜研究表明形成的薄膜表面平整光滑,没有微裂纹存在。扫描俄歇电子能谱及X射线光电子能谱的研究表明,Zr/Nb/Si薄膜样品具有清晰的界面结构。在薄膜表面形成了致密的氧化层物种,而在膜层内部少量氧则以吸附态形式存在。  相似文献   

17.
W-S-C films were deposited by non-reactive sputtering from a carbon target incrusted with WS2 pellets in the eroded zone. This process allows depositing coatings with a wide range of compositions, with a precise control of their carbon content. Before the deposition, a Ti interlayer was interposed between the film and the substrate to improve the final adhesion. The carbon content in W-S-C system was varied from 29 at.% to 70 at.%, which led to an hardness enhancement from 4 GPa up to 10 GPa where the maximum hardness was reached in films with a carbon content between 40 at.% and 50 at.%. The tribological behaviour of the coatings was evaluated by pin-on-disk testing, in environments with different humidity levels. Generally, the tribological performance of W-S-C coatings in environments with moderate to high humidity is better for coatings with high carbon content. Friction coefficients, as 0.05 or lower could be reached at low humidity ranges (<7%) to all compositions. However, for higher humidity values, friction coefficient increased up to 0.30 in the W-S-C film with low carbon content whereas it was kept approximately constant for the others compositions.  相似文献   

18.
Z.G. Zhang  O. Rapaud  D. Mercs  C. Coddet 《Vacuum》2008,82(11):1332-1336
Zirconium modified chromium nitride coatings with various Zr contents have been prepared by a DC reactive magnetron sputtering technique. The detailed investigations in terms of composition, phase structure, morphology and corrosion properties have been performed by GDOES, XRD, SEM and electrochemical measurements, respectively. The as-deposited coatings with Zr contents ranging from 0 to 3.2 at. % form nanocrystalline solid solutions, where Zr substitute Cr in the CrN lattice. With increasing Zr contents, the lattice parameters increase but the grain sizes show little effects. All the coatings exhibit dense compact columnar structures in SEM cross-sectional observations. Electrochemical measurements in 3.5% NaCl solutions revealed that the additions of Zr into CrN coatings improved their chemical inertness. The coated samples with much low corrosion current densities in nA/cm2 range show their excellent protective characteristics to the stainless steel substrates. The corrosion mechanism, however, was due to the slight pitting corrosions, which were mainly localized in the growth defects.  相似文献   

19.
为了进一步评价Zr含量对TiZrN薄膜摩擦学性能的影响,采用反应磁控溅射法制备了Ti_(1-x)Zr_xN薄膜(0.14x0.56)。通过XRD,SEM技术分析了TiZrN薄膜的微观结构,考察了不同Zr含量时TiZrN薄膜的摩擦磨损性能。结果表明:TiZrN薄膜的晶体结构不因Zr的加入而改变,仍为面心立方结构;TiZrN薄膜为合金化复合膜,Zr以置换方式固溶于TiN中,随着Zr含量的升高,晶粒明显细化,柱状晶生长模式发生转变;TiZrN薄膜结构致密且硬度更高,小晶粒在摩擦磨损中能有效阻止裂纹的扩展,其抗摩擦磨损性能较TiN薄膜有明显的提高。  相似文献   

20.
Mechanical and tribotechnical characteristics of composite multilayered coatings Zr–ZrN in air at temperatures from 20 to 900°C have been determined. The coefficient of friction of the Zr–ZrN coating against steel 65G has been found to exhibit a tendency toward decreasing as the velocity is lowered and the load is raised from 10 to 30 kgf. A study of properties of the coatings in the range between 20 and 900°C has demonstrated that hardness under a load of 1 kgf goes down gradually from 19 to 3.2 GPa. Hardness along the friction trace has been found to grow from 23 to 25 MPa, while hardness of the counterbody has increased twofold (from 4.5 to 9.0 GPa). The coefficient of friction of the composite multilayered coating Zr–ZrN against diamond at a velocity of 16 mm/s has been determined to range between 0.26 and 0.28.  相似文献   

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