不锈钢和Ti基体上Cu，Ag，Ni膜中的内应力研究

用电镀工艺在不锈钢基体上镀制了Cu,Ag,Ni膜的Ti基体上制备了Ni膜，并用悬臂梁法和X射法测量了膜中的残余应力。并基于改进的TFD模型，对任意膜厚下由界面电子转移引起的膜内应力作了理论估算。结果表明，理论估算所给出的膜内应力与实验测量值具有可比性，这说明理论计算模型具有较高的准确性和膜内残余应力主要由界面电子转移引起。     

基于电子理论的电镀薄膜内应力分析（英文）

用电镀方法在Fe、Ni和Ag基体上沉积Cu膜,在Fe和Ag基体上沉积Ni膜,在Cu基体上沉积Ag膜,在Fe基体沉积Cr膜,以及在Ag基体上沉积Ag膜,在Ni基体上沉积Ni膜和在Cu基体上沉积Cu膜。采用悬臂梁法原位测量了除Cr膜外其他薄膜的平均内应力。结果表明,薄膜和基体为异种材料时薄膜内界面应力很大,而为同种材料时界面应力为零。由悬臂梁的弯曲方向得到的界面应力的性质与由改进的Thomas-Fermi-Dirac电子理论得到的结果一致。     

测定膜基界面结合能的努氏印痕能量法

研究了涂层与基体界面结合能的测定方法，用理论和实验技术分析了努氏界面印痕法加载过程中，膜基试样吸收外加能量而转化为塑性变形能的行为、以及表面形状改变能和涂层界面断裂表面能，建立了努氏界面印痕能量法。对铁基Ni/Fe、镍基Cu/Ni低压等离子喷涂涂层进行界面结合强度的研究和分析得到涂层界面的断裂表面能。铁基纯镍Ni/Fe涂层界面的断裂表面能比镍基铜Cu/Ni涂层的高。界面微观分析表明：镍基铜Cu/Ni涂层材料疏松，膜基界面存在较多裂纹，涂层和基体中观察不到元素扩散层。Ni/Fe涂层界面结合致密，约有2μm的元素扩散层，微观分析现象与界面结合能的测定结果吻合。     

悬臂梁法测量不锈钢基体上铜膜和银膜残余应力

用悬臂梁法研究了不锈钢4Cr13基体上的Cu膜和Ag膜的平均残余应力和残余应力分布。结果表明，Cu膜和Ag膜的平均残余应力和分布残余应力随膜厚的增加而急剧减小。2种膜生长过程中界面应力很大，而生长应力很小。Cu膜在厚度较小时，残余应力值很大，超过了铜块材的断裂强度。     

基于电子理论Ni基体上电沉积Cu膜内应力研究

采用电沉积法在Ni基体上制备Cu膜。悬臂梁法在线测量沉积Cu膜后的Ni基片挠度,由测得的挠度值计算出Cu膜内的平均内应力和分布内应力。结果表明,Cu膜内的平均内应力和分布内应力均随膜厚的增加而急剧减小。膜内的界面应力很大,而生长应力很小。基于改进的Thomas-Feimi-Dirac-Cheng(TFDC)电子理论,对由于界面电子密度调整而引起的Cu膜内平均内应力作出了初步估算。结果表明,理论估算结果与实验结果较接近。这说明理论计算模型具有较高的准确性。     

调制波长对Cu／Ni金属多层膜力学性能的影响

用电沉积法在低碳钢基体上制备了具有不同调制波长(一个调制波长等于单层Cu膜与单层Ni膜厚度之和)的Cu/Ni金属多层膜，研究了多层膜硬度与其中单层膜厚度之间的关系。结果表明，当膜厚在亚微米范围内时，Cu/Ni多层膜的屈服强度(为硬度值的1/3)与单层膜厚之间符合基于位错塞积模型的Hall-Pctch(H-P)关系式；而当单层膜厚小于100nm时，屈服强度与膜厚的关系偏离了H-P线性关系。基于程开甲等人位错稳定性理论首次对金属多层膜变形行为偏离Hall-Petch关系的现象作了定量解释。     

压入深度与膜厚对薄膜与基体复合硬度及弹性模量的影响

根据高华建的复合弹性模量模型，提出了用一个测点的载荷-位移曲线计算整个压入深度内薄膜和基体复合硬度分布的方法，探讨了压入深度与膜厚对硬度与弹性模量测量值的影响，指出可由膜-基复合性能反推膜本身的性能。     

345MPa级耐候钢中Ni对Cu富集行为的影响

用扫描电镜和电子探针研究了含Ni和不含Ni两种成分的345 MPa级耐候钢的Cu富集行为。经1200℃保温2 h后,含Ni钢的氧化层较薄,厚度为132μm,大量白色富铜相在外氧化层中形成。在热轧除鳞时,含富Cu相的外氧化层脱落,热轧板表面形成较平整的二次氧化铁皮,钢板表面光滑。不含Ni耐候钢的氧化层较厚,为177μm,富Cu相主要在内氧化层中形成,并沿奥氏体晶界渗入基体。富Cu的内氧化层粘附于基体表面,不易随鳞脱落,在热轧时轧入基体,使得热轧板表面粗糙。本文通过试验分析提出了在钢中添加Ni避免热脆的机理。     

钛合金表面微弧氧化膜的特点及成膜分析

用微弧氧化方法在钛合金上形成二氧化钛薄膜，用扫描电镜、X射线衍射以及透射电镜分析了膜的组织结构和化学成分，用纳米压入仪和划擦仪测量了膜的硬度和弹性模量及划擦抗力。结果表明，钛合金表面形成一层微弧氧化膜，含有纳米晶结构。薄膜由晶体和少量非晶体组成，硬度和弹性模量分别为0．78GPa和35．6GPa，划擦过程中未出现膜从基体表面的剥落，但高载荷下膜本身有破坏和脱落。     

多孔不锈钢基体上钯膜沉积的制备研究

分别采用化学镀法、电镀法以及两者相结合的方式在孔径为5μm的多孔不锈钢基体上进行了致密钯膜的制备。采用SEM、EDS、XRD等对多孔不锈钢表面钯膜进行了表征。结果表明:以0.1 g/L的PdCl_2盐酸溶液对完成前处理的多孔不锈钢进行化学镀预镀后,再使用钯含量为17 g/L钯氨溶液进行电镀可制备出成分纯净的钯膜,此时,钯膜表面形貌平整致密且均匀,无明显坑洞和裂缝,膜厚10～20μm。     

Cu/Ni多层膜对Ti811合金微动磨损和微动疲劳抗力的影响

在Ti811钛合金表面利用离子辅助磁控溅射沉积技术制备20～1200nm不同调制周期的Cu/Ni金属多层膜,分析多层膜的结构,测试膜基结合强度、膜层显微硬度和韧性,对比研究不同调制周期的Cu/Ni多层膜对钛合金基材常温下微动磨损性能和微动疲劳(FF)抗力的影响。结果表明:利用离子辅助磁控溅射技术可以获得致密度高、晶粒细化、膜基结合强度高的Cu/Ni多层膜,该类多层膜具有良好的减摩润滑作用,因而改善了Ti811钛合金常温下抗微动磨损和微动疲劳性能;Cu/Ni多层膜对钛合金FF抗力的改善程度随膜层调制周期呈现非单调变化趋势,调制周期为200nm的Cu/Ni多层膜对钛合金FF抗力的提高程度最大,原因归于该膜层具有良好的强韧和润滑综合性能。     

磁控溅射Cu膜屈服强度的有限元计算

采用离子辅助轰击共溅射设备，在Si基体的(111)晶面上制得了所需的铜膜。采用纳米压入实验，获得不同退火温度下Cu膜的弹性模量和硬度。再在纳米压入实验的基础上，结合有限元模型计算不同退火温度下磁控溅射得到的Cu膜屈服强度。发现Cu膜的屈服强度远高于整体Cu材料的屈服强度，并且退火温度对薄膜的屈服强度影响很大。通过XRD测量发现其主要原因是退火改变了晶粒尺寸和多晶Cu膜的晶粒取向分布，而导致Cu膜屈服强度的降低。     

Ti90及其优化合金的组织与力学性能研究

研究了钎焊与时效过程中,在Sn0.7Ag0.5Cu(SAC0705)钎料与Cu基板和石墨烯Cu基板界面处金属间化合物(IMC)的形成与演变。采用加热平台制备焊接试样并在120℃时效600h。结果表明,界面金属间化合物在时效过程中增厚。SAC0705/Cu和SAC0705/G-Cu 2种焊接界面金属间化合物均为Cu6Sn5。当钎料中添加Ni元素后,Cu6Sn5化合物转变为(Cu,Ni)6Sn5。随着钎料中Ni元素含量的增大,2种基板上的界面金属间化合物厚度先增加后减小。此外,随着Ni含量增大,化合物生长速率降低。石墨烯Cu基板表面的石墨烯层起到扩散阻挡层效果,因此,石墨烯Cu板上的化合物厚度小于常规Cu基板,同时其界面化合物生长速率较低。     

Electron theory based explanation and experimental study on deformation behavior of Cu/Ni multilayers

Cu/Ni multilayers with various defined thickness of Cu and Ni layers were electrodeposited on low carbon steel substrates. Hardness measurements indicated that the increase in yield strength (one-third of hardness) with a decrease of layer thickness for Cu/Ni multilayers with single layer thickness at sub-micron length scale could be described by the Hall-Petch formula of the dislocation pile-up model. In the regime of few tens to a hundred nanometers of single layer thickness, the dislocation pileup-based Hall-Petch model broke down. This could be explained quantitatively according to the criterion condition on the limit size of dislocation derived from a modified Thomas-Fermi-Dirac electron theory.     

The influence of composition and processing parameters on the mechanical properties and erosion response of Ni + TiB2 coatings

Sputtered Ni + TiB₂ coatings have been shown to protect Inconel* 718 and Ti-6A1-4V substrates from solid particle erosion. However, before new erosion-resistant coatings can be efficiently designed, it is essential that the role of mechanical properties in determining erosion resistance be fully understood. In this investigation, nanoindentation techniques were used to quantify the effects of substrate preparation, coating composition, and sputtering process parameters on the elastic moduli and indentation hardness of thin coatings deposited on Ti-6A1-4V and Inconel 718 substrates. The influence of these parameters on coating adhesion was determined using a conventional scratch test. Elastic moduli, indentation hardnesses, and coating adhesion were correlated with erosion behavior. The erosion resistance of those coatings that exhibited microscopic ductility is dependent on the nodule diameter and coating properties such as hardness, elastic modulus, and fracture toughness. Inconel 718 is a trademark of The International Nickel Co.     

Effect of electrolyte pH and Cu concentration on microstructure of electrodeposited Ni-Cu alloy films

Single Ni and Ni-Cu alloy films were electrodeposited on polycrystalline Ti substrates from electrolytes with different pH values under potentiostatic control. The deposition processes of the films were evaluated by the current-time transients recorded during deposition. The analysis of the transients clearly showed that the initial deposition of Ni is affected by the electrolyte pH, while in the Ni-Cu alloys the Cu concentration of the electrolyte is more effective than the electrolyte pH. The microstructural analysis by X-ray diffraction (XRD) indicated that the texture degree in both Ni and Ni-Cu alloy films, which have face-centered cubic (fcc) structure, changes with the electrolyte pH. The surface morphology of the samples was investigated using the scanning electron microscopy (SEM) and atomic force microscopy (AFM). It was observed from SEM and AFM studies that the surface roughness of Ni deposits is not considerably affected by the electrolyte pH, while in Ni-Cu alloy films it changes significantly with both the electrolyte pH and the Cu concentration. Accordingly, the surface roughness of the Ni-Cu alloy films increased as electrolyte pH decreased and Cu concentration increased.     

Determination of interfacial fracture energies of Ni films on titanium and stainless steel substrates by peel test

The interracial fracture energy G, which includes the effect of residual stress, was deduced for Ni films on titanium and stainless steel substrates based on the energy-balance argument and the numerical method for the work expenditure Gdb of Moidu et al. The estimated interracial fracture energies G are independent of the film thickness, the peel angle and the residual stress. The value of G for Ni films on a stainless steel substrate is about 5.47-6.08N/m for various peel angles θ, while 5.33-6.72 N/m for Ni films on titanium substrate with various film thickness h. The effect of the residual stress on the peel strength P/b was also discussed.     

镍改性层增强铜基底沉积金刚石膜的形核(英文)

在铜基底溅射约100nm厚的镍改性层,然后置入纳米金刚石悬浮液中超声震荡加载籽晶,随后在热丝化学气相沉积设备中制备出晶体颗粒接近热力学平衡形态的高质量金刚石膜,其中sp2碳相含量低于5.56%。分别采用激光拉曼光谱、扫描电镜与X射线衍射对金刚石膜的形核与生长进行研究。实验结果表明:在溅射有镍改性层的铜基底上,金刚石的形核密度比在无改性层的铜基底上的形核密度高10倍。镍改性层的增强机制主要来源于两个方面:镍改性层的纳米级粗糙表面增强金刚石籽晶颗粒的吸附;镍改性层的强催化效应加速铜基底上金刚石形核生长所需的石墨过渡层的形成,从而促进金刚石的快速形核。     

亚微米厚铜薄膜的微观结构及疲劳损伤行为

在具有高弹性和力学稳定性的柔性基底上,用磁控溅射系统制备了亚微米厚铜薄膜,利用透射电镜（TEM）、扫描电镜（SEM）电子背散射成像及X射线衍射（XRD）对铜薄膜进行了微观结构表征．采用恒载荷幅控制研究了亚微米厚度铜薄膜的疲劳损伤行为．结果表明：退火后的铜薄膜呈现强烈的（111）织构,薄膜中存在大量的微米、纳米尺度孪晶．在恒载荷幅作用下,亚微米厚的薄膜不易产生疲劳挤出和微裂纹,疲劳裂纹容易在界面处萌生,孪晶附近的位错塞积及界面附近变形的不协调性导致了疲劳裂纹的产生．而亚微米厚铜薄膜疲劳强度的提高来源于薄膜厚度、晶粒尺寸和孪晶尺寸三个微尺度的约束．