舰船高性能防腐蚀防污涂料研究进展

简要论述了海洋防腐蚀防污涂料的发展历史和研究现状,重点论述了舰船高性能防腐蚀防污涂料的最新研究进展。有机锡自抛光防污涂料被禁止使用之后,基于丙烯酸锌、丙烯酸铜和丙烯酸硅烷酯的自抛光防污涂料得到了广泛应用。基于含防污功能基团树脂的防污涂料、基于降解树脂的防污涂料以及基于表面结构特性的防污涂料技术成为当前防污涂料研究的热点。文中详细报道了降解树脂的结构对降解性能及力学性能影响规律,以及表面结构特性对污损释放型防污涂料防污性能的影响规律。随着环境保护法规的日趋严格,防腐蚀涂料向无溶剂(或高固体)、长效方向发展。报道了提高涂层的湿态附着力和致密性的方法,采用该方法可以大幅提高涂层的力学性能和耐蚀性能,满足了远洋和深海装备发展需求。     

海洋船舶有机硅低表面能防污涂料的研究进展

海洋防污涂料是海洋工程与装备的重要防护材料,对于海洋资源开发利用发挥着极其重要的作用。在现用的海洋防污涂料中,低表面能防污涂料不会对海洋环境产生破坏,是将来的主要发展方向。本文简要介绍了低表面能防污涂料的机理及影响因素,重点论述了有机硅改性不同有机树脂的防污涂料、纳米材料改性有机硅防污涂料和有机硅仿生复合防污体系的技术发展现状,并展望了未来低表面能船舶防污涂料的发展方向。     

舰船防污涂料的使用需求及研究进展

海洋生物附着导致的生物污损是舰船航行过程中面临的一大难题,涂装防污涂料被认为是防止海洋生物污损舰船最经济有效的方法。根据舰船的服役特点,介绍了舰船防污涂料对于长效性、动静普适性和海域广谱性的使用需求,提出研发环保型长效防污涂料是当前防污损研究领域的一大挑战。简单综述了自抛光型防污涂料、污损释放型防污涂料、仿生型防污涂料、表面自愈型防污涂料以及其他防污新技术的发展,指出自抛光型防污涂料仍是当前稳定批量应用的主流产品,其他新型防污技术的防污期效仍需经过实际应用验证。随着环保要求的日趋严格,防污损机理研究的不断深入以及防污性能评价方法的不断完善,新型环保防污涂料的研制将逐渐加快并得到广泛推广应用。     

Al(Ni)含量对钛合金激光熔覆AlNiMoSi复合涂层摩擦学性能的影响

研究含Al、Si元素涂层的摩擦学性能可为其应用提供重要的理论参考。以Al、Ni、Mo、Si粉末为原料,采用激光熔覆技术在Ti6Al4V合金表面制备了Al质量分数分别为20%(Ni的为40%),30%(Ni的为30%),40%(Ni的为20%)的AlNiMoSi复合涂层,分别命名为20Al、30Al、40Al复合涂层。采用XRD、SEM和EDS分析了涂层的物相和显微组织,并测试了复合涂层的干滑动磨损性能。结果表明:20Al、30Al和40Al复合涂层的平均摩擦系数和磨损率分别为0.380,0.258,0.325和9.36×10~(-5),8.43×10~(-5),1.05×10~(-4)mm~3/(N·m),30Al复合涂层的磨损性能最好,主要是因为该涂层中TiC和Ti3Al含量较高;20Al和40Al复合涂层的磨损机理主要为黏着磨损和磨粒磨损,30Al复合涂层的磨损机理主要为轻微的磨粒磨损。     

等离子喷涂HA/Ti复合涂层研究 I.结构、组成和力学性能

采用等离子喷涂方法,在Ｔｉ－６Ａｌ－４Ｖ基体上成功地制备了ＨＡ／Ｔｉ复合涂层,并对复合涂层的微观结构,相组成和力学性能进行了研究。结果表明,ＨＡ和Ｔｉ两相均匀地分布于复合涂层中。ＨＡ／Ｔｉ复合涂层的结合强度明显高于纯ＨＡ涂层,这主要是由于ＨＡ／Ｔｉ的复合和了涂层与基体之间的热膨胀系数失配,ＨＡ／Ｔｉ复合涂层在模拟体液中浸泡一段时间后,结合强度没有明显降低,ＨＡ／Ｔｉ复合涂层的断裂韧性和硬度均高于Ｈ     

等离子喷涂HA/Ti复合涂层研究 I.结构、组成和力学性能

采用等离子喷涂方法,在Ｔｉ－６Ａｌ－４Ｖ基体上成功地制备了ＨＡ／Ｔｉ复合涂层,并对复合涂层的微观结构、相组成和力学性能进行了研究．结果表明,ＨＡ和Ｔｉ两相均匀地分布于复合涂层中．ＨＡ／Ｔｉ复合涂层的结合强度明显高于纯 ＨＡ涂层,这主要是由于 ＨＡ／Ｔｉ的复合缓和了涂层与基体之间的热膨胀系数失配．ＨＡ／Ｔｉ复合涂层在模拟体液中浸泡一段时间后,结合强度没有明显降低．ＨＡ／Ｔｉ复合涂层的断裂韧性和硬度均高于 ＨＡ涂层．     

冷喷涂铝/银纳米线复合涂层的海洋耐蚀防污性能研究

腐蚀和生物污损是海工装备长效服役面临的主要问题,也是海工装备防护的重点和难点.为此,提出了采用低成本水热法制备铝/银纳米线复合颗粒、利用冷喷涂的低温特性制备铝/银纳米线复合涂层的新思路,通过复合涂层成分和结构设计,构筑了致密的复合涂层;分别采用人造海水溶液和革兰氏阳性枯草芽孢杆菌评估了复合涂层的耐蚀和防污性能.结果表明...     

钎剂保护法WC／Cu基钎涂层的制备及其性能

目前,比较成熟的钎涂工艺基本上采用真空或气保护的方法,而仅以钎剂作保护实现钎涂加工的方法鲜有报道。为此,采用钎剂作保护,通过炉中钎焊的方法在Q235A钢表面制备了WC／Cu复合材料耐磨涂层,并通过组织观察和力学性能测试考察了钎涂层的性能。结果表明,使用粉状铜基钎料在大气环境下焊出的涂层气孔、渣孔等缺陷情况为：当涂层厚度...     

AZ91D镁合金有机复合涂层的腐蚀防护性能

AZ91D镁合金易腐蚀,单项处理防腐蚀效果不大。先分别对其作无铬转化和微弧氧化预处理,再阴极电泳底层,最后喷涂面漆,获得了无铬转化层/阴极电泳层/有机涂层和微弧氧化层/阴极电泳层/有机涂层。采用附着力及铅笔硬度测试、盐雾试验、电化学试验对2种有机复合涂层的形貌、多种性、防腐蚀效果及其机理进行了探讨。结果表明:2种有机复合涂层都能显著提高AZ91D镁合金的耐腐蚀性能,使其自腐蚀电位分别约提高130 mV和80 mV,腐蚀电流密度约降低40%和70%,极化电阻约提高4倍和7倍;2种涂层的附着力达到1级以上,铅笔硬度达到7 H以上;微弧氧化预处理后获得的有机复合涂层的腐蚀防护效果比无铬转化预处理的好。     

A corrosion study on W-Cu alloys in sodium chloride solution at different pH

A corrosion study of two types of tungsten-copper(W-Cu)alloys in 3.38 wt.%Na Cl solution with different pH at 25℃were investigated using potentiodynamic polarization and immersion test.It is crucial that the corrosion behavior and preferential attacked phases of the W-Cu alloys were found to alter with p H.The micro-galvanic effect of tungsten phase and copper binder played a significant role.It was also proved that the existence of aggressive chloride ions could accelerate the Cu binder dissolution in acidic and neutral solution,which induced tungsten phase detachment and increased the corrosion rate of the W-Cu alloys.While Cl-would accelerate the Cu binder dissolution of W-Cu alloys at high potential during polarization test in strong alkaline solution.     

Fabrication of nano-structured HA/CNT coatings on Ti6Al4V by electrophoretic deposition for biomedical applications

In order to improve the bone bioactivity and osteointegration of metallic implants, hydroxyapatite (HA) is often coated on their surface so that a real bond with the surrounding bone tissue can be formed. In the present study, cathodic electrophoretic deposition (EPD) has been attempted for depositing nanostructured HA coatings on titanium alloy Ti6Al4V followed by sintering at 800 degrees C. Nano-sized HA powder was used in the EPD process to produce dense coatings. Moreover, multiwalled carbon nanotubes (CNTs) were also used to reinforce the HA coating for enhancing its mechanical strength. The surface morphology, compositions and microstructure of the monolithic coating of HA and nanocomposite coatings of HA with different CNT contents (4 to 25%) on Ti6Al4V were investigated by scanning-electron microscopy, energy-dispersive X-ray spectroscopy and Xray diffractometry, respectively. Electrochemical corrosion behavior of the various coatings in Hanks' solution at 37 degrees C was investigated by means of open-circuit potential measurement and cyclic potentiodynamic polarization tests. Surface hardness, adhesion strength and bone bioactivity of the coatings were also studied. The HA and HA/CNT coatings had a thickness of about 10 microm, with corrosion resistance higher than that of the substrate and adhesion strength higher than that of plasma sprayed HA coating. The properties of the composite coatings were optimized by varying the CNT contents. The enhanced properties could be attributed to the use of nano-sized HA particles and CNTs. Compared with the monolithic HA coating, the CNT-reinforced HA coating markedly increased the coating hardness without deteriorating the corrosion resistance or adhesion strength.     

Bioconductivity and mechanical properties of plasma-sprayed dicalcium silicate/zirconia composite coating

Dicalcium silicate (C₂S)/yttria stabilized zirconia (YSZ) composite coatings possessing better durability and more superior mechanical properties than pure C₂S coatings were produced by atmospheric plasma spraying. The microstructure and phase composition of the composite coatings were determined by scanning electron microscopy and X-ray diffraction. The bioconductivity of the coatings was evaluated in vitro by incubating in simulated body fluids (SBF). Apatite was observed to precipitate even on coatings comprising more than 70% YSZ after immersion in SBF for 7 days. The changes of the mechanical properties of the composite coatings due to immersion in SBF were also investigated. The durability was found to increase with a larger YSZ content in the coatings. Deterioration of the mechanical properties can be attributed to the degraded interlamellar or cohesive bonding due to fast dissolution of C₂S. This study reveals factors affecting the durability of the C₂S/YSZ composite coatings in simulated physiological environment and suggests means for improvement to address clinical needs.     

电子束重熔对机械合金化法制备TiC/Ti复合涂层组织及摩擦性能的影响

对机械合金化（MA）法制备的TiC/Ti复合涂层进行电子束重熔处理,分析了经过不同电子束扫描速度的重熔工艺后TiC/Ti复合涂层组织和耐磨性能的变化规律。结果表明,当扫描速度为5~15 mm/s时,重熔处理消除了MA法制备的TiC/Ti复合涂层中的孔隙和裂纹,使其硬度与耐磨性能显著提高;但扫描速度过快（20 mm/s）时,TiC/Ti复合涂层内部出现重熔导致的孔洞缺陷。随着扫描速度由5 mm/s增加至15 mm/s,重熔后TiC/Ti复合涂层中的TiC相由粗大树枝状晶体逐渐转变为弥散分布的短棒和颗粒状晶体,弥散强化作用和固溶强化作用逐渐增强,TiC/Ti复合涂层的硬度由重熔前HV 554逐渐提高至HV 783,磨损速率由5.93×10-4 mm3（N·m）-1逐渐下降至1.75×10-4 mm3（N·m）-1,扫描速度为15 mm/s重熔后TiC/Ti复合涂层的性能最佳。      

纤维涂层法制备SiCf/Cu复合材料及其性能分析

为研究纤维涂层法制备SiCf/Cu复合材料的性能特点,通过磁控溅射法先后将Ti6Al4V界面改性层和基体Cu涂层涂覆到SiC纤维表面,并通过真空热压法将被涂覆的纤维制备成SiCf/Cu复合材料.对Ti6Al4V涂层、Cu涂层以及复合材料进行了微观分析,并测试了复合材料的拉伸强度.研究表明,复合材料的Cu基体由致密而细小的晶粒组成;Ti6Al4V提高了纤维/基体界面结合强度,复合材料轴向抗拉强度高达500 MPa,界面脱粘主要发生在纤维表面的碳涂层与纤维之间.     

Antifouling mechanism of natural product-based coatings investigated by digital holographic microscopy

Using natural product-based antifouling coatings has proven to be an effective strategy to combat biofoul-ing.However,their antifouling mechanisms are still unclear.In this study,the antifouling mechanism of natural product-based coatings consisting of bio-sourced poly(lactic acid)-based polyurethane and eco-friendly antifoulant(butenolide)derived from marine bacteria was revealed by observing 3D bacterial motions utilizing a 3D tracking technique-digital holographic microscopy(DHM).As butenolide content increases,the density of planktonic marine bacteria(Pseudomonas sp.)near the surface decreases and thus leads to a reduced adhesion,indicating that butenolide elicits the adaptive response of Pseudomonas sp.to escape from the surface.Meanwhile,among these remained cells,an increased percentage is found to undergo subdiffusive motions compared with the case of smaller dose of butenolide.Further experiments show that butenolide can accelerate their swimming velocity and reduce flick frequency.Antibacterial assay confirms that butenolide-based coating shows high efficacy of antifouling performance against Pseudomonas sp.but without killing them like 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one(DCOIT).     

等离子喷涂NiCrBSi增强Mo涂层的组织结构和断裂韧性

为了开发既具有较高硬度、可防止黏着磨损、又具有一定孔隙能够储存润滑油的用于气缸内壁和活塞的热喷涂层,采用等离子喷涂制备了纯Mo和Mo-28%NiCrBSi复合涂层,采用图像法定量表征了涂层的孔隙率,采用压痕法测试了涂层的硬度和断裂韧性,研究了添加NiCrBSi对等离子喷涂Mo层的组织结构、孔隙率、硬度和断裂韧性的影响,并与某进口防黏着磨损Mo涂层进行比较。结果表明:等离子喷涂Mo-28%NiCrBSi复合涂层的孔隙率比纯Mo涂层略高,硬度为(561±83)HV3 N,比纯Mo涂层提高19%,比服役过的进口纯Mo涂层高约40%;复合涂层的断裂韧性为8.9 MPa"m1/2,约为纯Mo涂层的4倍,接近Mo块材。     

"渗氮/物理气相沉积"复合涂层研究的新进展

介绍了"渗氮/物理气相沉积(PVD)"复合涂层在涂层结构设计、工艺与性能、失效与强化机制等方面研究的最新进展.与单一涂层相比,"渗氮/PVD"复合涂层表现出更好的物理力学性能,明显提高了工模具的耐用性.渗氮层的引入不仅显著地提高了基材表面的承载能力和膜/基结合力,而且还提高了钢表面的疲劳强度、耐磨性能、热冲击及化学抗力,尤其是在承受高载荷情况下的失效抗力.经过十几年的研发,复合涂层已开始进入商业应用阶段,在高速钢切削刀具和各种精密工模具上有广阔的应用前景.     

Composite calcium phosphate coatings with sustained Zn release

Zinc-substituted tricalcium phosphate/fluoridated hydroxyapatite (ZnTCP/FHA) biphasic composite coatings and Zinc containing fluoridated hydroxyapatite (ZnFHA) coating were prepared on Ti6Al4V substrates through a modified sol-gel method. The release of zinc ions from these coatings was characterized through a designed cycled immersion test: the coatings were soaked in the TRIS solution with pH of 7.25 at 37 °C for 96 h (one cycle). This process was repeated twice with the solution refreshed at the end of the each cycle. The Zn concentrations were measured at a 24-hour interval during the first cycle and at the end of each cycle. The results indicated that ZnTCP/FHA coatings released Zn at a rather slow and sustained rate while ZnFHA coatings released Zn at a rapid and therefore unsustained rate. This Zn release behavior difference is attributed to the different chemical states of Zn in the coatings. The current results demonstrated that the designed biphasic composite approach could potentially be a good way to tailor the release of Zn through combinations of different Zn chemical states, with the durability of the coatings not impaired.     

The effects of metal coating on the diffusion bonding in Al2O3/Inconel 600 and the modulus of rupture strength of alumina

Alumina with a sputter-deposited metal film was diffusion bonded to Inconel 600. A higher bonding strength and lower joining temperature were obtained with titanium coating compared to that for the non-coated sample. The improved joining behaviour was attributed to an enhanced interface reaction and reduction in the thermal stress. Also, the effect of various coatings of 3 m thickness on the mechanical property of alumina after heat treatment at 1000 °C for 30 min under 10^–6 torr vacuum was evaluated in terms of modulus of rupture (MOR) using a Weibull plot. While the Cu coating did not change MOR strength of alumina, the reactive Ti and Zr metal coatings caused a noticeable reduction in averaged MOR strength. The effect of co-sputtering of Ti-Cu, and bilayer coatings of Cu/Ti and Ti/Cu was also investigated.     

Fabrication,characterization and wear corrosion testing of bioactive hydroxyapatite/nano-TiO2 composite coatings on anodic Ti–6Al–4V substrate for biomedical applications

This study elucidated structure and mechanical properties of the electroplated hydroxyapatite/nano-TiO₂ composite coatings on Ti–6Al–4V alloy. Their effect on the corrosion and wear corrosion resistance in Hanks’ solution was examined as well. The anodizing process was performed on Ti–6Al–4V alloy surface to enhance the adhesion of these composite coatings on Ti alloy. Anodizing treatment was then conducted at 10 V at room temperature with different times of 40, 50, 60, 120 and 180 min. Experimental results indicate that the hardness of Ti–6Al–4V alloy was increased due to the anodizing treatment, capable of improving the adhesion of electroplated calcium phosphate coating in addition to the electroplated hydroxyapatite/nano-TiO₂ composite coatings. Additionally, the coatings on anodic substrate exhibited a higher uniformity and Ca/P ratio and thickness than that on nonanodized substrate. The nano-TiO₂ particles could be co-deposited on the Ti–6Al–4V alloys and capable of reinforcing the hydroxyapatite coating, subsequently increasing the hardness and refining the structure. Moreover, the corrosion and wear corrosion resistance of the electroplated hydroxyapatite/nano-TiO₂ composite coatings were also improved significantly when increasing the duration of anodizing alloy substrates.