调质结构对Ti-TiN-Zr-ZrN多层膜力学性能影响

采用真空阴极电弧离子镀技术,在TC11钛合金和单晶Si片表面分别沉积不同调制周期、不同R_Ti/TiN:R_Zr/ZrN调制比和不同厚度的Ti-TiN-Zr-ZrN多层膜。用扫描电镜、X射线衍射仪、划痕仪、显微硬度计和应力测试仪分析测试了多层膜的截面形貌、厚度、结合力、硬度和残余应力;重点研究了调制周期、调制比和膜层厚度等调制结构的改变对多层膜残余应力和相关性能的影响。结果表明：增加调制周期,则残余应力降低,结合力和硬度均增大;降低RTi/TiN:RZr/ZrN调制比,则残余应力增大,结合力下降,硬度增加;增大多层膜厚度,则残余应力略有上升,结合力和硬度都提高,当膜层厚度达到7.54μm后,硬度稳定在30Gpa左右。     

调制周期对CrAlN/ZrN纳米多层膜韧性的影响

目的研究调制周期对纳米多层膜性能的影响。方法采用磁控溅射方法制备了CrAlN与ZrN的固定厚度比为2.6,不同调制周期(Λ为6,8,10,20 nm)的CrAlN/ZrN纳米多层膜。利用场发射扫描电镜(FESEM)表征薄膜的形貌、结构。用Dektak150型台阶仪测薄膜表面粗糙度。用Agilent Technologies G200纳米压痕仪检测涂层的硬度和弹性模量。用划痕仪测薄膜/基材的结合力,同时,引入抗裂纹扩展系数(CPR)表征纳米多层膜的韧性。结果 CrAlN/ZrN纳米多层膜断面皆为穿晶柱状结构,调制周期为20 nm时,多层膜层与层之间的界面清晰;多层膜表面呈致密的花椰菜状,厚度均约为2μm。调制周期为8 nm时,硬度为20.4 GPa,进一步增大调制周期,硬度下降。调制周期为8 nm的多层膜临界载荷L_(c2)为18 N,CPR值为73.2,L_(c2)与CPR值均高于其他调制周期的多层膜。在临界载荷L_(c2)处,裂纹扩展导致薄膜发生了严重的片状剥落,露出了亮白的热轧钢基底,薄膜失去了保护作用。结论实验表明,在多层膜厚度、调制比不变的条件下,改变调制周期能够改变多层膜的韧性。随着调制周期的增大,韧性呈先上升、后下降的趋势。调制周期为8 nm时,纳米多层膜的硬度最高,韧性最好,综合性能良好。     

医用316L不锈钢支架表面沉积(Fe/Pd)n薄膜的研究

采用真空电弧离子镀技术,在医用316L不锈钢支架上沉积近等原子比的(Fe/Pd)n多层膜.用X射线衍射、扫描电镜、电子能谱研究(Fe/Pd)n多层膜的晶体结构、形貌和成分,分析相的转变.用CTCC-1数字磁通磁场测量仪测量样品的磁性.结果表明:医用316L不锈钢支架表面磁性膜的最佳结构为"Pd/Fe/Pd",经扩散热处理后,(Fe/Pd)n薄膜从fcc结构转变为fct结构,薄膜均匀、致密、结合强度良好,有效磁场强度可达5×10-4 T以上,有效磁性可维持6个月.     

自支撑Ti/Al纳米多层膜激光诱发自蔓延行为

通过磁控溅射法并借助有机高分子牺牲层,制备了具有不同调制结构的自支撑Ti/Al(调制比为1)纳米多层膜.采用脉冲激光诱发了纳米多层膜的自蔓延反应,确定了临界诱发能量密度.利用高速摄影法表征了自蔓延速度,采用SEM和TEM观察了纳米多层膜结构,利用差热分析仪和XRD分析了反应过程及产物.结果表明,纳米多层膜激光诱发临界能量密度(6~17 J/cm2)高于烧蚀临界能量密度.调制周期或周期数较小的纳米多层膜激光诱发所需的能量密度较小且自蔓延速度较高.但当调制周期接近或小于层间原子互溶区厚度时,临界能量密度和自蔓延速度的变化则有相反趋势.对于一定厚度的纳米多层膜,具有大调制周期和小周期数的调制结构对应的放热量大.随激光脉冲持续时间的延长,Ti/Al纳米多层膜的激光临界诱发能量密度呈现递减趋势,但最终趋于稳定.激光诱发Ti/Al纳米多层膜自蔓延反应生成单一的TiAl金属间化合物.     

调制周期对Cr/CrN纳米多层膜的结构与性能的影响

采用多弧离子镀技术在65Mn钢表面制备了不同调制周期的Cr/CrN纳米多层膜.采用俄歇能谱仪(AES)、扫描电子显微镜(SEM)、X射线衍射仪(XRD)、纳米硬度仪、轮廓仪和划痕仪,分析了不同调制周期Cr/CrN纳米多层膜的成分分布、微观结构、力学性能、残余应力和结合强度.结果表明,Cr/CrN纳米多层膜的表面平整致密,截面层状调制结构清晰,其调制结构为Cr层-过渡层-CrN层的"三明治"结构,调制比约为1∶ 1.多层膜由CrN、Cr2N和Cr相组成,在CrN(200)方向上出现择优取向.当调制周期为80 nm时,多层膜的硬度值相对较高.随调制周期的增大,Cr/CrN多层膜的残余应力值减小,结合强度值先增大后减小.当调制周期为120 nm时,涂层的划痕临界载荷值相对较高,为69 N.     

双槽电沉积法制备Cu/Ag纳米多层膜

双槽电沉积法制备了不同调制波长的Cu/Ag金属多层膜(Cu膜和Ag膜等厚),用扫描电子显微镜观察了多层膜的层状结构,并研究了不同调制波长下多层膜的显微硬度变化.结果表明:双槽电沉积法制备的Cu/Ag多层膜层状结构明显.当调制波长大于100 nm时,显微硬度随调制波长减小而增加;当小于100 nm时,硬度随调制波长减小而...     

TiAlN/CrAlN纳米结构多层膜的结构与性能

采用射频磁控溅射方法制备了单层TiAlN、CrAlN复合薄膜以及不同调制周期和不同层厚比(lTiAlN/lCrAlN)的TiAlN/CrAlN纳米结构多层膜.薄膜采用X射线衍射仪、扫描电子显微镜、显微硬度仪进行表征.结果表明:TiAlN、CrAlN复合薄膜和TiAlN/CrAlN多层膜均为面心立方结构,呈(111)面择优取向.TiAlN/CrAlN多层膜的择优取向与调制周期和层厚比无关.层厚比为1的TiAlN/CrAlN多层膜的硬度依赖于调制周期,在调制周期为8 nm时,达到最大;固定TiAlN的厚度为4 nm,改变CrAlN层的厚度,在研究范围内,多层膜的硬度随着CrAlN层厚度的增加而增加.探讨了多层膜的致硬机制.TiAlN/CrAlN多层膜抗氧化温度比其组成单层膜高了近200 ℃,并讨论了其抗氧化机制.     

超高真空电子束蒸镀Fe/Ru多层膜的结构和磁性

采用超高真空电子束蒸镀方法制备了Fe/Ru多层膜,Ru层厚度固定为2 nm,Fe层厚度为0.6～5 nm,研究了Fe层厚度的变化对薄膜结构及其磁性能的影响.Fe层厚度小于5 nm时,受Ru层HCP结构的影响,Fe层生长为六方晶格的亚稳相.多层膜呈现明显的平面易磁化特性,并随Fe厚度降低而减弱.Fe的平均原子磁矩和Fe层厚度的倒数存在线性关系,与死层理论预言的结果相一致.实验结果证实,亚稳相六方晶格的Fe具有铁磁性,其平均原子磁矩计算值为1.9μB,略低于BCC Fe,Fe/Ru界面层的死层厚度为0.25 nm.     

磁控溅射制备Fe／Ti多层膜的结构和磁性

用磁控溅射技术制备了系列Fe／Ti纳米多层膜，周期调制在2．2-24．0nm；用透射电镜和小角，高角X射线衍射分别研究了样品的结构；用振动样品磁强计和Mossbauer谱研究了样品的磁性，发现铁层厚度在2nm附近时存在铁磁性面心立方γ-Fe，样品的易磁化方向平行于膜面；随调制周期增大，样品的饱和磁化强度增加，矫顽力下降且与结晶状态有关。     

溅射沉积Cu/W纳米多层膜结构与性能

以单晶硅和聚酰亚胺为衬底,用磁控溅射沉积调制周期λ=25~150 nm、调制比η=0.5~2的Cu/W纳米多层膜,用XRD、SEM、EDS、AFM、微力测试系统、纳米压痕仪和四探针法对多层膜微观结构、表面形貌和力学及电学性能进行研究。结果表明:λ和η显著影响多层膜结构和性能。多层膜Cu层和W层均为纳米晶结构,分别呈Cu(111)和W(110)择优取向。W(110)晶面间距减小且减幅与1/λ或η值呈正相关,Cu/W层间界面处存在扩散混合层。表面Cu层晶粒尺寸随Cu层厚增加而增大。裂纹萌生临界应变εc总体上随λ增大或η减小而下降,屈服强度σ0.2、显微硬度H和电阻率ρ总体上均与λ或η呈负相关。因Cu层和W层厚度随λ或η的变化而改变,相应地改变了Cu层晶粒度及其晶界密度、W层体积分数和Cu/W层间界面数量,使位错运动能力及电子散射效应变化,最终改变Cu/W纳米多层膜性能。     

STRUCTURE AND MAGNETIC PROPERTIES OF Fe/Pd COMPOSITIONALLY MODULATED FILMS

Metal Fe/Pd compositionally modulated films(CMFs) were prepared by vapour depo-sition from two sources onto glass substrate under vacuum.The modulation and crystalstructures of the films were examined by X-ray diffraction.The magnetic properties weredetermined by vibrating sample magnetometer.The Pd layers in the Fe/Pd CMFs areof fcc structure,and the Fe layer structure transits from bcc into amorphous,state withdecreasing thickness of Fe layer.The dependence of specific saturation magnetizationon thickness of Fe layers has also been discussed.     

Structural transition and magnetic properties of evaporated Fe/Gd multilayers

Fe/Gd multilayers were prepared by alternate vapor deposition of pure Fe and Gd at a rate of 0.01-0.03 nm/s in an ultra-high-vacuum electron-gun evaporation system.The effects of the constituent metal layer thickness on the microstructures and magnetic properties of the films were investigated by low angle X-ray diffraction,transmission electron microscopy,and vibrating sample magnetometer.The experimental results show that a transition from the polycrystalline to amorphous state in the Fe layers occurs with the decrease of Fe layer thickness in the Fe/Gd multilayers.The saturation magnetization of the muitilayers reduces significantly with decreasing Fe layer thickness and increasing Gd layer thickness.A superparamagnetic behavior at room temperature is observed for the [Fe(0.6 nm)/Gd(4.0 nm)]15 multilayer due to the formation of discontinuous Fe layers.     

MAGNETIC PERFORMANCE TRANSITION IN Fe/Tb MULTILAYERS INDUCED BY INTERFACE ROUGHNESS

1. IntroductionIn the past decade, metastable phaJses have been fOund in various multilayers when thedeposited nonequilibrium phases have same crystal structure as the substrate. On suitablesubstrate and under moderate environments it is possible to induce growth of metastablephases. An example is the epitaxial growtli of fcc Fe on fcc Cu substrate where bothelements have close atomic .i...Il'2]. Since the substrate has same crystal structure asthe nonequilibrium phase, the lower interface e…     

气相沉积铁钇多层膜的磁学性能

研究了气相沉积技术制备的Fe/Y多层膜的磁学性能,试验结果表明,当多层膜中铁层厚度减少到1．4nm时,薄膜由铁磁性转变为超顺磁性;多层膜的饱和磁化强度随铁层厚度的减少和钇层厚度的增加而显著降低。     

Magnetic properties and structure of Ni80Fe20/Ni48Fe12Cr40 bilayer films deposited on SiO2/Si（100） by electron beam evaporation

Ni80Fe20/Ni48Fe12Cr40 bilayer films and Ni80Fe20 monolayer films were deposited at room temperature on SiO2/Si（100） substrates by electron beam evaporation. The influence of the thickness of the Ni48Fe12Cr40 underlayer on the structure, magnetization, and magnetoresistance of the Ni80Fe20/Ni48Fe12Cr40 bilayer film was investigated. The thickness of the Ni48Fe12Cr40 layer varied from about 1 nm to 18 nm while the Ni80Fe20 layer thickness was fixed at 45 nm. For the as-deposited bilayer films the introducing of the Ni48Fe12Cr40 underlayer promotes both the （111） texture and grain growth in the Ni80Fe20 layer. The Ni48Fe12Cr40 underlayer has no significant influence on the magnetic moment of the Ni80Fe20/Ni48Fe12Cr40 bilayer film. However, the coercivity of the bilayer film changes with the thickness of the Ni48Fe12Cr40 undedayer. The optimum thickness of the Ni48Fe12Cr40 underlayer for improving the anisotropic magnetoresistance effect of the Ni80Fe20/Ni48Fe12Cr40 bilayer film is about 5 nm. With a decrease in temperature from 300 K to 81 K, the anisotropic magnetoresistance ratio of the Ni80Fe20 （45 nm）/Ni48Fe12Cr40 （5 nm） bilayer film increases linearly from 2.1% to 4.8% compared with that of the Ni80Fe20 monolayer film from 1.7% to 4.0%.     

316L不锈钢血管内支架表面Fe/Pd磁性膜的制备与生物学效应

以医用316L不锈钢血管支架为基体,采用电弧离子镀技术在其表面制备Fe/Pd磁性薄膜.通过激光扫描共焦显微镜、数字磁通磁场测量仪分析薄膜的表面形貌、表面粗糙度及表面磁性膜支架的磁性能,并通过动物体内实验研究Fe/Pd磁性膜支架的生物学效应.结果表明:Fe/Pd磁性膜支架表面光滑,并具有良好的生物学效应,显著地促进了血管内皮再生,同时有效地抑制了血管内膜过度增生和血管壁的炎症反应.     

Fe/Ru界面对多层膜磁性的影响

采用高分辨透射电镜结合振动样品磁强计研究了Fe/Ru多层膜,对不同层厚的Fe/Ru多层膜的界面结构及其对磁性能的影响进行了分析。Fe层很薄时薄膜不连续,岛状分布的Fe颗粒使多层膜显示超顺磁特性。Fe/Ru界面的高分辨电镜观察发现,界面存在粗糙度的不对称性,它是多层膜中产生正磁阻的重要原因。Fe/Ru多层膜的负磁阻在退火后得到较大的提高,表明Fe/Ru多层膜的负磁阻主要来源于界面的粗糙度。     

The effect of multilayer structure on magnetic properties of FePt thin films

The Fe/Pt multilayer films with different structures were deposited by RF magnetron sputtering on glass substrates, and the L1₀-FePt films were obtained after theas-deposited samples were subjected to vacuum annealing at various temperatures. Results show that the Fe/Pt multilayer structure can effectively reduce the ordering temperature of FePt film, and the in-plane coercivity of [Fe (5.2 nm)/Pt (5.2 nm)]₇ multilayers can reach 161.2 kA/m after annealed at 350 ℃ for 30 min. When Fe and Pt layer thickness is equal, the coercivity of the film is the largest. On the other hand, the different Fe-Pt crystalline phases such as Fe₃Pt and FePt₃ phases are formed after annealing when the thickness ratio of Fe/Pt deviates from 1 after annealing. When Fe and Pt have the same thickness, the thinner single layer gets the lower ordering temperature and the larger coercivity.     

磁控溅射Pd膜对Zr70Fe5.4V24.6合金吸/放氢性能的影响

采用磁控溅射技术在Zr70Fe5.4V24.6(质量分数,%,下同)合金基体上沉积Pd膜。研究磁控溅射沉积Pd膜的生长特性和显微组织及Pd膜对Zr70Fe5.4V24.6合金吸/放氢性能的影响规律。结果发现,在Zr70Fe5.4V24.6合金基体上磁控溅射沉积的Pd膜具有fcc结构并在(111)晶面有明显的择优取向。对镀膜后合金吸/放氢性能的测试结果表明,磁控溅射沉积Pd膜对Zr70Fe5.4V24.6合金的活化性能及吸氢动力学无显著影响。沉积Pd膜后Zr70Fe5.4V24.6合金可逆吸氢量H/A由0.63增至1.20,吸氢平台增长量约为90%。氢化物形成焓绝对值的平均值增大约77%,生成熵的平均值增大约56%,沉积Pd膜后的合金与氢结合所形成的氢化物更稳定。     

Electrodeposition of multi-layer Pd–Ni coatings on 316L stainless steel and their corrosion resistance in hot sulfuric acid solution

Pd–Ni coating shows good corrosion resistance in strong corrosion environments. However, in complex aggressive environments, the performance of the coatings is limited and further improvement is necessary. The effects of the applied plating current density on the composition, structure and properties of Pd–Ni coatings were studied. By changing the current density in the same bath, multi-layer Pd–Ni coatings were prepared on 316L stainless steel. Scanning electronic microscopy, weight loss tests, adhesion strength, porosity and electrochemical methods were used to study the corrosion resistance of the films prepared by different coating methods. Compared with the single layer Pd–Ni coating, the multi-layer coatings showed higher microhardness, lower internal stress, lower porosity and higher adhesive strength. The multi-layer Pd–Ni coating showed obviously better corrosion resistance in hot sulfuric acid solution containing Cl^?.