Adhesion of Sputtered Nickel Films on Polycarbonate Substrates

Nickel films were deposited by radio frequency magnetron sputtering on top of polycarbonate substrates. Surface energy of the substrate was measured by means of the contact angle technique. Effects of sputtering parameters on the critical load between the film and the substrate were determined by the universal mechanical testing system. Optimized fabrication parameters and their influence on the critical load between sputtered nickel films and polymer substrate were studied by means of the orthogonal experimental design. Increasing radio frequency power and time improved film critical load. The radio frequency power had a more pronounced effect on critical load than the sputter power. The plasma pretreatment with Ar gas modified the surface, leading to an increased surface energy, improving the chemical bonds between nickel and carbon atoms, and thereby enhanced the critical load. The adhesion mechanism is also discussed in this paper.     

TiO_2基薄膜溶胶-凝胶法制备

介绍了以钛酸丁脂为前驱物,掺入或不掺入Ｆｅ２Ｏ３和Ｍｎ２Ｏ３,用溶胶－凝胶法在玻璃表面成功地制备出ＴｉＯ２基薄膜。比较了不同含水量和催化剂量对溶液溶胶－凝胶转变性质的影响。简要地讨论了溶胶－凝胶过程中,水解和缩聚的化学机制,并用ＸＲＤ谱、ＩＲ谱等方法研究了玻璃表面薄膜性能。     

颗粒增强铝基复合材料断裂韧度研究

采用搅熔复合法制备颗粒增强铝基复合材料．对复合材料断裂韧度进行了测试。系统研究了影响该材料断裂韧度的各种影响因素：结果表明：在增强相加入量相同时．采用Sic颗粒复合材料的断裂韧度比Al2O3的影响显著，而增强颗粒质量分数越高．则复合材料的断裂韧度越低．增强颗粒尺寸越小，复合材料断裂韧度值越大。热处理状态对断裂韧度也有较大影响，人工时效比自然时效状态下的断裂韧度高。     

激光沉积修复TA15钛合金断裂韧度研究

采用激光沉积修复技术对预损伤TA15钛合金锻件进行修复,研究基材、激光沉积试样、体修复试样以及面修复试样的断裂韧度.采用光学显微镜和扫描电子显微镜分析试样的微观组织、断裂表面以及纵截面形貌.结果 表明:基材呈现双态组织,修复区呈现网篮组织,热影响区表现为从双态组织到网篮组织的转变.激光沉积试样、体修复试样以及面修复试样...     

基体材料对TiN薄膜表面液滴及薄膜结合力的影响

采用真空阴极电弧离子镀技术分别在4Cr5 MoSiV1(H13)模具钢、Cr18Ni9Ti(304)不锈钢、YG6硬质合金、Ti6Al4V(TC4)钛合金4种基体表面沉积TiN薄膜.利用扫描电镜(SEM)对薄膜表面液滴进行观察分析,通过划痕仪对薄膜的膜/基结合力进行表征.结果表明:基体材料不同,TiN薄膜上液滴的密度、尺寸存在明显的区别.其中,镀膜后H13钢和304不锈钢表面的液滴数量最多,YG6硬质合金次之,TC4钛合金最少;薄膜的膜/基结合强度依次为YG6硬质合金＞H13钢＞304不锈钢＞TC4钛合金.     

High Temperature Tribological Properties of Ti-GLC Films Deposited on Different Bearing Steel SubstratesEI北大核心CSCD

针对航空发动机主轴轴承服役工况恶劣和类石墨碳基薄膜在高温环境下的性能研究不足等问题,采用磁控溅射技术在不同轴承钢基体(M50 钢、M50NiL 钢和 W9Cr4V2Mo 钢)上沉积 Ti-GLC 薄膜,探究在不同温度下的摩擦学性能。采用 SEM、 Raman 分析薄膜的微观结构,采用纳米压痕仪、划痕仪等测试其力学性能,利用 MFT-5000 型多功能摩擦磨损试验机测试所镀薄膜在不同温度下(室温、200 ℃、250 ℃和 300 ℃)的摩擦学性能。结果表明：在三种不同轴承钢基体沉积的 Ti-GLC 薄膜,其硬度和弹性模量变化不大,结合力从大到小依次为 M50＞M50NiL＞W9Cr4V2Mo。随着温度的升高,三种钢基体沉积 Ti-GLC 薄膜的摩擦因数均逐渐增大,而磨损率则先减小后增大,且表现出不同的磨损形式。三种轴承钢基体沉积 Ti-GLC 薄膜的最佳工作温度区间为室温~200 ℃,M50 钢基体所镀薄膜具有更好的力学性能和摩擦学性能,其结合力达到 80 N 以上, 300 ℃时的平均摩擦因数为 0.125,磨损率仅为 3.05×10^?17 m³ /(N·m)。研究成果为类石墨碳基薄膜在高温环境下的实际应用奠定了理论基础。     

采用热丝CVD法在多种基材上沉积金刚石薄膜

热丝法是一种比较成熟的气相合成金刚石膜的方法,其其它方法比较,热丝法在工艺参数对金刚石薄膜的结构和质量的影响、界面的形成、薄膜生长各阶段的特征等方面的基础研究及各种应用研究上有其特征的优越性。本文采用热丝法在ＳｉＣ昌须增强Ｓｉ３Ｎ４陶瓷、ＡＩＮ陶瓷、Ｓｉ单晶片、Ｍｏ片等基材上沉积出金刚薄膜,并通过ＴＥＭ和ＳＥＭ进行观察,分析和研究了影响金刚石薄膜沉积的因素．     

柔性基底上直流磁控溅射沉积金属铝膜的研究

采用直流磁控溅射法在棉布、涤纶、芳纶织物上制备金属铝膜,研究了铝膜的沉积速率、组织结构和表面形貌。结果表明:在一定的范围内,沉积速率随溅射功率的增大近似呈线性增加,随溅射气压的增加先升后降;基底材料对铝膜的组织结构有较大影响,在涤纶和棉布上沉积的铝膜才呈现出典型的多晶态面心立方结构,在芳纶和涤纶上获得的铝膜较棉布上的铝膜更为均匀、致密;在一定范围内,溅射功率的增大有助于提高铝膜质量。     

紫外光截止镀膜玻璃的射频磁控溅射法制备及表征

制备了摩尔比为1：1的TiO2和CeO2陶瓷靶材。采用射频磁控溅射法在O2和Ar比例为5：95的混合气体中制备了玻璃基TiO2-CeO2薄膜。溅射过程中，工作气压保持在1．8Pa不变，玻璃基片温度从室温（RT）～220℃之间变化。用x射线衍射（XRD）、X射线光电子能谱（XPS）、扫描电镜（SEM）、透射电镜（TEM）和紫外-可见光谱仪研究了薄膜的物相结构、表面组成、表面形貌和镀膜试样的紫外-可见光透过率。结果表明，薄膜表面结构平滑、致密，呈微小晶粒结构，薄膜中Ti和Ce仅以Ti^4＋和Ce^4＋的形式存在；随着基片温度升高，薄膜中的细小晶粒略有长大；TiO2-CeO2镀膜玻璃可以有效地截止紫外线。     

Crystal-Structure-Based Modeling Study of Temperature-Dependent Fracture Toughness for Brittle Coating Deposited on Ductile Substrate

The temperature-dependent fracture toughness of a brittle coating/ductile substrate system, WC-10Co4Cr deposited on 1018 low carbon steel, is evaluated at microscopic level using an indentation-based model in terms of the Arrhenius-type equation and rate-controlling theory. The formulation of the model utilizes the parameters of crystal structures of each phase in the coating material. The slip systems of hard hexagonal \( \updelta \)-WC phase and soft FCC \( \upalpha \)-Co phase are analyzed. The fracture toughness of the two-phase coating is obtained by integrating the fracture toughness of single \( \updelta \)-WC phase coating and that of single \( \upalpha \)-Co phase coating using either the basic mixture method or the unconstrained mixture method. The results suggest that the fracture toughness of WC-10Co4Cr coating/1018 low carbon steel substrate system may remain constant until the temperature reaches a critical value, about 200 K, and ranges from 2.16 to 10.82 \( {\text{MPa}}\;{\text{m}}^{1/2} \), with temperature increasing from room temperature (298 K) to 1000 K.     

Splat Formation and Adhesion Mechanisms of Cold Gas-Sprayed Al Coatings on Al2O3 Substrates

The metallization of ceramics by means of cold gas spraying (CGS) has been in the focus of numerous publications in the recent past. However, the bonding mechanism of metallic coatings on non-ductile substrates is still not fully understood. Former investigations of titanium coatings deposited on corundum revealed that a combination of recrystallization induced by adiabatic shear processes and hetero-epitaxial growth might be responsible for the high adhesion strengths of coatings applied on smooth ceramic surfaces. In the present work, the interface formation between CGS aluminum and alumina substrates is examined for different particle sizes and substrate temperatures. Furthermore, the influence of subsequent heat treatment on tensile strength and hardness is investigated. The splat formation of single particles is examined by means of scanning electron microscopy, while a high resolution transmission electron microscope is used to study the Al/Al₂O₃ interface. First results suggest that mechanical interlocking is the primary adhesion mechanism on polycrystalline substrates having the roughness in sub-micrometer range, while the heteroepitaxy between Al and Al₂O₃ can be considered as the main bonding mechanism for single-crystalline sapphire (α-Al₂O₃) substrates with the surface roughness in nanometer range. The heteroepitaxial growth is facilitated by deformation-induced recrystallisation of CGS aluminum.     

薄膜材料断裂韧度的准连续介质法预测

本文通过二维准连续介质法模拟三角型压头在纳米压痕试验中测量铝薄膜材料断裂韧度的过程,得到了相应的载荷-位移曲线,计算出了铝薄膜在纳米尺度下的断裂韧度(KIC)和相关的力学性能参数.数值结果显示:单晶铝薄膜材料在纳米尺度下的断裂韧度(KIC)为0.216MPa.m1/2,预测值与相关试验结果较吻合,从而表明使用准连续介质法预测纳米尺度下薄膜材料的断裂韧度是可行的.在研究中发现:对应于载荷-位移曲线的急剧下降区域,相应的位移云纹图中有明显的压痕变形集中现象,表明此处是径向裂纹发生的准确位置.计算结果证明,这种载荷-位移曲线和位移云纹图相结合的方法是计算薄膜材料径向裂纹的有效方法.     

微喷砂预处理对硬质合金上沉积类金刚石薄膜结合力的影响

针对镀前不能使用高能离子轰击清洗的硬质合金工件,采用正交法设计微喷砂工艺,用320目白刚玉对YG6硬质合金样品进行微喷砂预处理后,利用阳极层流型气体离子源和非平衡磁控溅射复合技术制备梯度过渡类金刚石薄膜.结果表明:类金刚石薄膜厚度为2.7 μm,平均显微硬度高达2 677 HV_(0.025,15),平均摩擦因数低至0.105;未预处理的硬质合金样品的膜/基结合力为30 N,而微喷砂预处理后的样品,其膜/基结合力显著提高,最高可达55.7 N;微喷砂各个因素对膜/基结合力的影响程度不同,其中喷砂压力是主要影响因素,喷砂距离和喷砂时间影响较小;优化后的微喷砂预处理工艺参数是:喷砂压力:0.10 MPa;喷砂距离:75 mm;喷砂时间:120 s.     

合金元素Al对Laves相NbCr2显微组织及断裂韧性的影响

采用机械合金化+热压烧结的工艺路线制备Laves相NbCr2合金,研究合金元素Al对其显微组织、力学性能,特别是韧化效果的影响.结果表明:合金元素Al主要占据了Laves相NbCr2金属间化合物中Cr原子的晶格位置.添加合金元素Al的Laves相NbCr2合金较未合金化的NbCr2硬度有所提高;当Al含量达到12at%时,断裂韧性要高于未合金化的NbCr2合金,达到了6.8 Mpa√m,远远高于熔铸合金的断裂韧性(1.2 Mpa√m).     

铌-铬复合溅射膜对锆合金基体的附着性

研究了铬膜和铌膜的复合对锆合金基体上制备的商流磁控溅射薄膜附着性的影响。使用扫描电镜(SEM)观察了膜层界面，用原子力显微镜(AFM)观察了膜层表而，用划痕法测定了薄膜的附着性。结果表明：膜／基界面结合良好，界面成分升降区狭窄；铬膜与铌膜组成的复合薄膜结合紧密；铬膜的组织为致密、边界孔洞少的纤维状晶粒，铬膜厚度为2μm时，晶粒仍为业微米级，但晶粒顶而已出现拱形；膜厚同为2μm时，外层1μm铌膜 内层1μm铬膜组成的复合膜的附着性分别是外层1μm铬膜 内层1μm铌膜组成的复合膜的2．35倍、2μm铬膜附着性的3倍，其原因在于膜层组织及力学性能变化、铌膜韧性好和复合顺序。因此，依靠铬膜厚度的增加米提高铬膜保护性的方法具有较大局限性，通过在一定厚度的铬膜外复合铌膜的方法则有较好的可行性。     

金刚石薄膜膜基界面结合强度测量技术的研究进展

膜基界面结合强度的测量与评价是金刚石薄膜制备与应用关键问题，本文介绍了国内外金刚石薄膜膜基界面结合强度的几种典型的测量方法，着重探讨了膜基界面结合强度的精确定量测量技术的研究现状以及发展趋势，提出了用一种新的内涨鼓泡测量法，对复杂形状基体上金刚石薄膜膜基界面结合强度进行精确定量检测，为金刚薄膜的制备工艺优化及其质量的评估提供可靠的依据和标准。     

原位模板法在铝基底上制备TiO2纳米管阵列薄膜

采用液相沉积法，将铝基多孔阳极氧化铝（AAO）模板浸入到（NH4）2TiF6溶液中，制备出高度有序的TiO2纳米管阵列薄膜，并在不同的温度下进行了热处理。用场发射扫描电子显微镜、透射电子显微镜和X射线衍射仪等手段对试样的微观形貌、结构及物相进行了表征。结果表明，TiO2纳米管的形貌依赖于AAO的特征，薄膜是由外径大约200nm，壁厚约40nm的TiO2纳米管阵列组成，薄膜厚度约25μm。原位模板法制备的TiO2纳米管阵列薄膜为非晶态，在400℃空气中焙烧2h转变为锐钛矿相TiO2。经过650℃焙烧仍保持纳米管结构，表现出较好的热稳定性。     

Improved Fracture Toughness of Cryorolled and Room Temperature Rolled 6082 Al Alloys

In the present work,6082 Al alloy has been rolled to 40% and 70% thickness reductions at the cryogenic and room temperatures for the improvement in mechanical and fracture toughness properties.All cryorolled samples are subjected to aging at different temperatures,i.e.,140,160,and 190 °C to improve the strength,ductility,and fracture toughness.The microstructures of the cryorolled(CR) and room temperature rolled(RTR) alloy after 40% and 70%thickness reductions are characterized by FE-SEM to reveal the modes of failure.The results show that the starting bulk Al alloy specimen is fractured in total ductile manner,consisting of well-developed dimples over the entire surface.The mechanical properties and fracture toughness of the 70% CR alloy are found better than 70% RTR alloy due to higher dislocations density and formation of sub-grain structures in the CR alloy.     

ADI的冲击韧度和断裂韧度

论述了ADI的冲击韧度和断裂韧度。室温有缺口和无缺口ADI的冲击韧度比铸钢,锻钢要略差,但约是普通珠光体球铁的3倍,ADI的冲击韧度虽随温度降低而降低,但在-40℃条件下仍保持大约室温冲击韧度的70%。断裂力学性能是更重要的安全设计和失效分析依据,无论哪一种断裂韧度,ADI的试验数据都好于普通球铁,相当于或好于强度相当的铸钢和锻钢。     

不同氧源对原子层沉积ZnO薄膜的性能影响

采用原子层沉积方法(ALD)分别以H2O、H2O2和O3为氧源制备ZnO薄膜,研究不同氧源对ZnO薄膜生长速率、成分、晶体结构及电学性能的影响.结果表明,采用不同氧源均能实现ZnO薄膜的ALD自限制生长,所制备ZnO薄膜均具有垂直于衬底表面的c轴择优取向.与采用H2O2和H2O为氧源制备的ZnO薄膜相比,XRD和XPS测试证实O3为氧源制备薄膜的晶体质量和Zn/O原子较高;相应的Hall测试表明其电阻率最低为0.053 Ω·cm,此时载流子浓度为4.8×1018 cm-3,Hall迁移率为24.5 cm2/Vs.