热喷涂金属陶瓷涂层摩擦磨损性能研究进展

随着热喷涂技术的发展,热喷涂金属陶瓷涂层在摩擦磨损领域得到了广泛应用。简要介绍了金属陶瓷颗粒的特征和常用热喷涂金属陶瓷涂层技术。然后从热喷涂方法、工艺参数和粉末特征3方面阐述了金属陶瓷涂层的制备和结构,重点评述了热喷涂金属陶瓷涂层摩擦磨损性能的研究进展,最后对热喷涂技术制备性能优异的耐磨损金属陶瓷涂层的要求进行了系统总结。     

热喷涂陶瓷-树脂复合涂层的研究现状

陶瓷-树脂复合涂层兼具陶瓷材料和树脂材料的优异性能,具有良好的力学性能、摩擦磨损性能、耐腐蚀性能等,可用于防腐、减摩等领域,是当前热喷涂领域的新兴研究方向。如在先进航空发动机制造领域,通过在陶瓷涂层中添加树脂材料以增加涂层孔隙率,使高温可磨耗封严涂层的可磨耗性显著提升。然而,陶瓷与树脂的热物理性质和化学性质差异较大,导致复合涂层沉积时粒子的熔融沉积行为呈现复杂多样性,对涂层性能的影响规律尚不清晰。目前,国内外对陶瓷-树脂复合涂层的制备和应用开展了大量的研究,在不同热喷涂方法下,陶瓷材料和树脂材料对复合涂层结构、性能的影响取得了显著成果。基于此,本文综述了采用火焰喷涂、等离子喷涂、反应等离子喷涂三种热喷涂技术制备陶瓷-树脂复合涂层的国内外相关研究;比较分析了喷涂过程中,不同热喷涂技术对陶瓷材料与树脂材料的影响规律;梳理了等离子喷涂工艺的优化方法;展望了未来陶瓷-树脂复合涂层的研究重点与应用方向。     

新型热喷涂及其复合技术的进展

热喷涂由于可以在基体上快速获得性能优良的涂层而受到人们广泛关注.针对研究热点冷喷涂技术、低压等离子喷涂薄涂层、液体热喷涂技术的研究及其应用做了详细介绍,同时也介绍了热喷涂与激光复合技术的一些研究进展.此外,对近年来热喷涂领域中的新型喷涂设备的发展和前沿进行了文献综述,以期推动国内热喷涂技术的研究开发与应用.     

热喷涂制备纳米涂层的研究进展

介绍了热喷涂制备纳米涂层的方法,主要是间接喷涂法和直接喷涂法.并简要介绍了国内外研究动态和水平,分析了热喷涂制备纳米涂层所面临的一些难题及现有的解决方法和措施,展望了热喷涂技术在未来制备纳米涂层方面的发展.     

热喷涂纳米结构涂层技术的研究进展

与传统材料的热喷涂涂层相比,纳米结构涂层在力学和摩擦学等方面的性能有了一定的提高.作者综述了国内外在应用热喷涂技术制备纳米结构涂层方面的研究进展.介绍了纳米结构喂料的制备、热喷涂纳米结构涂层的构筑方法、涂层的特殊性能以及应用情况.从目前国内外的情况来看,热喷涂纳米结构涂层技术的研究取得了较大的进展.随着技术、工艺的不断完善,其必将在很多领域取代传统的涂层.     

热喷涂技术的研究进展及思考

综述了热喷涂技术的基本概念,喷涂层的成型过程原理以及热喷涂的发展历史与现状。从喷涂方法、材料配比和工艺参数等方面介绍了防腐蚀涂层、抗高温氧化涂层、耐磨性涂层、热障涂层和生物涂层的研究进展,并阐述了上述功能涂层的应用原理,最后展望了热喷涂技术的研究方向。     

空气超音速火焰喷涂、冷喷涂与电镀制备电触头银层的组织结构与摩擦磨损性能对比

电触头是电力输送系统中的关键元器件,其失效方式与触头表面涂层的磨损密切相关。采用空气超音速火焰喷涂工艺(HVAF)和冷喷涂工艺(CS)分别制备了银涂层;采用往复摩擦试验研究了涂层在不同载荷、频率条件下的摩擦磨损性能,并与电镀银镀层的性能进行了对比;采用扫描电镜(SEM)和X射线能谱仪(EDS)研究了涂层磨痕的表面形貌和成分,并对涂层的摩擦磨损机理进行了分析和讨论。结果表明：空气超音速火焰喷涂和冷喷涂工艺均可制备较厚的致密银涂层;冷喷涂制备的银涂层硬度较高,在高频、高载荷条件下具有较小的摩擦系数和较低的磨损量;空气超音速火焰喷涂和冷喷涂制备的银涂层的磨损机制主要为疲劳磨损。     

热喷涂Zn-Al合金防腐涂层技术的研究进展

热喷涂Zn-Al合金涂层技术是一项新发展起来的防腐技术.介绍了近年来分别利用火焰喷涂技术和电弧喷涂技术制备Zn-Al合金涂层及其喷涂材料的研究应用现状,分析了涂层的形成及其耐蚀机理,并展望了热喷涂Zn-Al合金涂层技术的发展趋势.     

热喷涂纳米涂层制备方法及材料研究现状和展望

综述了热喷涂纳米涂层的制备方法现状及所用材料的发展情况,介绍了溶液等离子喷涂(SPS)、冷气动力喷涂(CGDS)、高速火焰喷涂(HVOF)技术制备纳米涂层的优势、纳米粉末材料的制备方法及发展趋势,指出纳米涂层制备的主要关键在于解决纳米粉末的输送技术和涂层制备过程中抑制纳米颗粒的长大趋势.纳米涂层的研究对推动热喷涂技术应用有着十分重要的作用.     

镁合金表面热喷涂铝基涂层研究进展

介绍了镁合金表面热喷涂技术的特点及国内外采用热喷涂技术为镁合金表面提供Al涂层防护的研究现状,指出了镁合金表面热喷涂技术获得Al涂层在防护中存在的不足,从喷涂工艺和喷涂材料的角度分析了镁合金表面热喷涂Al涂层技术的发展趋势,并提出了今后镁合金表面热喷涂Al涂层防护工作需要解决的两个主要问题:降低热喷涂Al涂层的孔隙率和从材料本身提高Al涂层的耐磨防腐性能。     

Thermisch gespritzte Beschichtungen für den Armaturenbau

This study discusses the development of various thermally sprayed coatings for the use in the valve industry. Based on established coating systems for wear protection, different solid lubricants were integrated into these coatings in order to optimize the wear and friction behavior at application oriented loads. Wear protection coatings based on WC/CoCr and Cr₃C₂/NiCr were applied. As solid lubricants, nickel-encapsulated graphite and hexagonal boron nitride were investigated. The thermal spraying processes high velocity oxygen fuel flame spraying (HVOF) and the novel ultra high velocity flame spraying (UHVOF) were investigated. The results show that through an appropriate coating composition a wear reduction of 53 % and a friction reduction of 31 % are possible.     

Al2O3陶瓷爆炸喷涂涂层性能分析

使用爆炸喷涂法制备了Al2O3陶瓷涂层,以自熔性NiAl合金粉末作为底层,基体为45钢。涂层的XRD图谱分析表明,爆炸喷涂的Al2O3陶瓷涂层结构以α-Al2O3及γ-Al2O3为主,说明在爆炸喷涂中存在相变过程;使用国标JB/T7509-94铁试剂方法进行测定,Al2O3陶瓷涂层孔隙率为0.019个/mm2,爆炸喷涂的Al2O3陶瓷涂层结构致密;滑动磨损试验说明,爆炸喷涂Al2O3陶瓷涂层提高了钢基体的耐磨损性能,适用于耐磨涂层。     

热喷涂喷焊层的抗磨性研究

热喷焊和热喷涂技术被广泛用于机件的耐磨强化，按涂层材料和工艺和不同会得到不同组织和性能的涂层，研究评价这些涂层在磨粒磨损和冲蚀磨损中的抗磨能力及规律性，可为工程应用提供一定的指导。     

Anisotropic Thermal Diffusivities of Plasma-Sprayed Thermal Barrier Coatings

Thermal barrier coatings (TBCs) are used to shield the blades of gas turbines from heat and wear. There is a pressing need to evaluate the thermal conductivity of TBCs in the thermal design of advanced gas turbines with high energy efficiency. These TBCs consist of a ceramic-based top coat and a bond coat on a superalloy substrate. Usually, the focus is on the thermal conductivity in the thickness direction of the TBC because heat tends to diffuse from the surface of the top coat to the substrate. However, the in-plane thermal conductivity is also important in the thermal design of gas turbines because the temperature distribution within the turbine cannot be ignored. Accordingly, a method is developed in this study for measuring the in-plane thermal diffusivity of the top coat. Yttria-stabilized zirconia top coats are prepared by thermal spraying under different conditions. The in-plane and cross-plane thermal diffusivities of the top coats are measured by the flash method to investigate the anisotropy of thermal conduction in a TBC. It is found that the in-plane thermal diffusivity is higher than the cross-plane one for each top coat and that the top coats have significantly anisotropic thermal diffusivity. The cross-sectional and in-plane microstructures of the top coats are observed, from which their porosities are evaluated. The thermal diffusivity and its anisotropy are discussed in detail in relation to microstructure and porosity.     

Keramik-Polymer Kombinationsschichten

Ceramic Polymer Composite Coatings The tribological properties of ceramic-polymer composite coatings which consist of thermal sprayed oxide ceramics coated with polymer lacquers for numerous industrial applications are discussed in this paper. The surface of these coatings match the requirements of high wear resistance and low coefficient of friction which is desired for many industrial applications. For experimental evaluation, samples were fabricated by coating aluminum substrates with titanium dioxide by means of atmospheric plasma spraying (APS). This oxide ceramic surface was successively coated by means of air spraying with a polymer lacquer containing molybdenum disulphide (MoS₂) and polytetrafluor ethylene (PTFE) as solid lubricants. The tribological properties (coefficient of friction and wear) of this combination layer were determined using a tribometer under oscillating sliding movement.     

Friction moment prediction of HVOF coatings and Electroplated Hard Chromium

Wear is one of the most critical problems in mechanics, oil, and gas industries among other industrial fields. Electrolytic Hard Chromium (EHC) and HVOF thermal spraying for applications of various materials have proved to be effective against wear. In this study, the results of wear tests for WC-12Co, Cr₃C₂-25NiCr, Tribaloy©-400, and EHC are predicted and compared using an artificial intelligence methodology. It has been shown that predicted wear analysis permits to determine friction moment for different loading conditions. The best candidate seems to be WC-12Co for which worn surface reveals prevailing adhesion mechanism responsible for the lowering of the friction moment.     

磷光粉表面包覆对铜基磷光复合材料发光及摩擦性能影响

选用热稳定性好的SiO2为包覆物,采用溶胶-凝胶法,以正硅酸乙酯为硅源,对商用磷光粉SrAl2O4∶Eu2+,Dy3+表面进行包覆,以解决磷光粉在高温下制备复合材料过程中因与金属粒子接触以及高温氧化产生猝灭的问题。实验通过热压烧结制备块体铜基磷光复合材料,考评包覆工艺对高温下制备的复合材料发光及摩擦性能的影响。通过X射线衍射、扫描电镜、荧光分光仪等设备对包覆前后磷光粉的表面形貌和发光性能进行分析和表征,采用摩擦试验机对包覆前后磷光粉与高铝青铜粉末混合制备复合材料烧结试样的摩擦性能进行研究。结果表明磷光粉表面包覆可有效避免其在高温下氧化猝灭和接触猝灭,包覆后磷光粉应用于铜基复合材料中可有效降低复合材料的磨损量,提高材料的耐磨性,当包覆比为10%时复合材料的发光性能、耐磨损性能最佳。     

A comparative study on thermally sprayed alumina based ceramic coatings

Aluminium oxide is relatively cheap material, abundant almosteverywhere and therefore it is widely used for thermal sprayapplications. Various alumina based powder containing 13 wt. Titania, two different 40 wt.% Zirconia and three differentcompositions of alumina-zirconia-chromia were deposited byatmospheric plasma spraying (APS) and high power plasma spraying(HPPS). The coatings obtained were evaluated by optical microscopy,microhardness measurements, X-ray diffraction and porositymeasurements. Moreover, abrasion and friction wear resistance wereevaluated by using Pin-on-Disc machine. Microhardness values of APScoatings are relatively high as compared to HPPS coatings except inalumina-zirconia-chromia coatings. HPPS have higher hardness values.APS coatings are much coarser and show higher porosity values thanHPPS coatings. The best wear/friction behaviour exhibited coatingAl₂O₃-40 wt.% ZrO₂ that deposited from agglomerated andsintered powder type.     

Cr3C2-NiCr涂层对水力机械材料耐磨蚀性能影响研究

以水力机械材料中的A3钢为基体材料,选取UDS-200全自动爆炸喷涂系统为喷涂设备,通过不同喷涂功率在A3钢表面喷涂了5种不同孔隙率的Cr₃C₂-NiCr涂层样品。采用FE-SEM和显微硬度计,研究了Cr₃C₂-NiCr涂层样品的表面形貌和显微硬度;通过摩擦磨损试验和中性盐雾腐蚀试验,研究了Cr₃C₂-NiCr涂层样品对水力机械材料的耐磨性能和耐腐蚀性能的影响。结果表明,实施摩擦磨损后,Cr₃C₂-NiCr涂层样品表面的磨痕部位比其余部位更为光滑,磨痕呈现清晰的条纹状;Cr₃C₂-NiCr涂层样品的摩擦系数呈现先升高后降低的趋势,升高和降低的波动幅度较小,摩擦系数基本稳定在0.6左右;Cr₃C₂-NiCr涂层属于脆性材料,其质量磨损率与摩擦角度和摩擦速度成正比,而与摩擦温度成反比,孔隙率越高耐磨性能越差;Cr₃C₂-NiCr涂层样品的孔隙率越高,耐腐蚀性能就越差;随着孔隙率的逐渐提升,Cr₃C₂-NiCr涂层样品的失重量和失重速率均不断提升;喷涂层数越多,则Cr₃C₂-NiCr涂层的腐蚀速率越低,耐腐蚀性能越好,能够更好地保护水力机械材料不被介质腐蚀。     

滑靴耐磨减摩涂层制备

目的制备减摩耐磨涂层,使滑靴在高速干摩擦条件下运动时能够减弱由于颗粒磨损、表面凿削和高温热烧蚀而引起的烧蚀和磨损。方法使用超音速火焰喷涂技术,在滑靴滑轨同材料试样上喷涂NiCr-Cr_3C_2耐磨涂层,并且加入不同质量分数的Ni包MoS_2粉末对涂层性能进行优化,接着通过对制得的涂层进行硬度、结合强度、摩擦磨损系列试验,对比各项试验结果得到了最优粉末质量分数配比,从而使制得的涂层在具有耐磨基础的同时也能达到减摩的效果。结果对涂层进行各种性能表征,综合各种试验结果可得出,选择Ni包MoS_2的质量分数为16%～24%之间时,涂层的综合效果最好。结论制得的涂层应用在滑靴摩擦表面上不仅可以使滑靴基体的表面温升缓慢,还能够极大程度上降低热烧蚀的发生,有效解决了滑靴高速运动下由于温升而使材料气化的问题。