热喷涂纳米陶瓷涂层的研究现状及进展

热喷涂技术是制备纳米结构陶瓷涂层最具前途的方法之一.本文简要介绍了热喷涂陶瓷涂层的性能、研究现状,并对热喷涂纳米陶瓷涂层面临的问题进行了讨论.     

纳米复合涂层的制备和性能研究进展

综述了纳米复合涂层的制备工艺，包括热喷涂、纳米复合镀、纳米粘结粘涂技术、纳米复合涂料技术等；介绍了纳米复合涂层在提高材料力学性能、耐腐蚀性、光学、电学、磁学等方面的性能研究，展望了纳米复合涂层的发展。     

纳米陶瓷热喷涂若干问题的试验研究

就制备Al2O3-3TiO2纳米陶瓷涂层的热喷涂系统热源，焰流速度和纳米陶瓷棒进行了试验研究，提出了采用低温、高速、强力、纳米陶瓷棒制备纳米陶瓷涂层的热喷涂工艺。     

金属表面纳米粒子/聚合物复合防腐涂层的研究进展

纳米材料（NMs）具有独特的性能，由其构成的纳米粒子/聚合物复合涂层在金属表面防腐蚀方面是非常经济有效的。本文总结了氧化物基和碳基两种不同纳米材料对纳米粒子/聚合物涂层性能的影响，概述了典型纳米粒子/聚合物复合防腐涂层防腐机理，表明碳基纳米材料可以作为提高防腐涂层阻隔性能的较有前途的纳米填料。最后展望了将纳米粒子/聚合物材料有效应用到金属表面防腐涂层中所面临的挑战和未来发展前景。     

新世纪的纳米科技以及在表面工程的应用

纳米科技在新世纪具有重要的战略地位，纳米科技的研发引起了世界各国的高度重视，新的纳米科技研究成果不断涌现。本文在简述纳米科技的战略地位和基本性能的基础上，重点阐述了纳米材料的电刷镀，热喷涂等表面工作中的应用以及取得的一些研究成果，同时提出了纳米材料在表面工程领域的应用将成为表面工程新的重要发展方向。     

碳纳米材料固相微萃取涂层的制备及应用

固相微萃取技术的核心是涂层,发展高选择性、高稳定性和高效的新型涂层材料及其相关的制备技术是固相微萃取技术发展的关键。碳纳米材料由于其独特的理化特性作为萃取介质已在样品前处理领域得到广泛应用,其中,碳纳米管和石墨烯更是研究热点。本文对近年来碳纳米材料包括碳纳米管、石墨烯、富勒烯、纳米碳纤维、碳纳米球固相微萃取涂层的制备技术及其应用的研究进展进行了简要评述。     

热喷涂陶瓷涂层

综述了陶瓷涂层的热喷涂制备方法、工艺特点、性能评价以及陶瓷涂层在各领域中的应用，分析了热喷涂陶瓷涂层存在的问题和解决方法，并对其发展趋势进行了展望。     

浙江省研制纳米改性封闭剂

最近，“钢桥梁电弧喷涂层纳米改性封闭剂研制及工艺性能研究”课题通过了专家鉴定。鉴定委员会认为，其成果总体上达到了国际先进水平，其中将纳米材料用于改性热喷涂封闭涂料技术属国际领先。     

纳米材料及其应用前景

纳米材料由于其独特的表面效应，全积效应以及量子尺寸效应，使得材料的电学，力学，磁学，光学等性能产生了惊人的变化，纳米技术在精细陶瓷，化工，微电子学，生物工程，医学等领域的成功应用及其广阔的应用前景，使得纳米材料及其技术成为目前科学研究的热点之一，被认为是21世纪的又一次产业革命。     

新型辅助喷涂设备的开发

随着热喷涂技术的提高和喷涂设备的发展以及人体卫生的需要，自动化喷涂是现代喷涂发展的趋势，这同时也满足了高质量涂层的需要，对热喷涂行业产业化发展有重要的意义。     

Thermal properties of plasma-sprayed thermal barrier coating with bimodal structure

Nanostructured zirconia coatings have been prepared by atmospherical plasma spraying (APS) on NiCrAlY-coated superalloy substrates. The isothermal oxidation test results indicate that the oxidation kinetics of nanostructured TBC follows a parabolic law and the oxidation resistance of the nanostructured TBC is comparable to that of the conventional TBC. The nanostructured thermal barrier coatings exhibit excellent thermal cyclic resistance and low thermal diffusivity. The failure of the nanostructured TBC occurs within the top coat and close to the YSZ/thermal growth oxide interface. The thermal diffusivity of the coating is 90% of that of conventional thermal barrier coatings, and it increases after heat treatment at 1050 °C for 34 h. The increase in the thermal diffusivity of the coating is ascribed to grain growth, the crack healing as well as sintering neck formation.     

Microstructural,mechanical and tribological properties of nanostructured YSZ coatings produced with different APS process parameters

Plasma sprayed ceramic coatings can be used in turbine engines as thermal barrier or abradable coatings, in order to improve the durability of the components as well as the efficiency. The presence of nanostructures, deriving from partial melting of agglomerated nanostructured particles, represents an interesting technological solution in order to improve their functional characteristics. In this work nanostructured yttria stabilized zirconia (YSZ) coatings were deposited by air plasma spraying (APS). The influence of the main process parameters on their microstructural, mechanical and tribological properties was investigated by scanning electron microscopy (SEM), indentation techniques at micro- and nano-scale and wear tests, respectively. Their porous microstructure was composed of well melted overlapped splats and partially melted nanostructured areas. This bimodal microstructure led to a bimodal distribution of the mechanical properties. An increase of plasma power and spraying distance was able to produce denser coatings, with lower content of embedded nanostructures, which exhibited higher elastic modulus and hardness as well as lower wear rate.     

Novel-structured plasma-sprayed thermal barrier coatings with low thermal conductivity,high sintering resistance and high durability

The microstructure of the ceramic topcoat has a great influence on the service performance of thermal barrier coatings (TBCs). In this study, conventional layered-structure TBCs, nanostructured TBCs, and novel-structured TBCs with a unique microstructure were fabricated by air plasma spraying. The relationship between the microstructure and properties of the three different TBCs was analysed. Their thermal insulation ability, sintering resistance, and durability were systematically evaluated. Additionally, their failure modes after being subjected to two kinds of thermal shock tests were analysed. The results revealed that the novel-structured TBCs had remarkably superior performances in all the examined aspects. The thermal conductivity of the novel-structured TBCs was significantly lower than those of the conventional and nanostructured TBCs both in the as-sprayed state and after thermal treatment for 500 h at 1100 °C. The macroscopic elastic modulus of the novel-structured TBCs after sintering at 1300 °C for 100 h was similar to those of the conventional and nanostructured TBCs in the as-sprayed state. During both a burner rig thermal shock test and a furnace cyclic oxidation test, the thermal shock lifetime of the novel-structured TBCs was much longer than those of the conventional and nanostructured TBCs. This study has demonstrated novel-structured plasma-sprayed TBCs with high thermal insulation ability and high durability.     

关注陶瓷材料在汽车上的热喷涂新技术

陶瓷材料热喷涂是一项具有广泛实用性的新型表面处理和表面强化的专业技术,具有许多金属材料无法比拟的优异性能,所以发展迅速,在许多领域发挥了越来越重要的作用。目前已在汽车及其他许多领域中成功应用,其技术的开发有着非常广阔的前景。针对陶瓷材料的喷涂新技术展露头角,介绍了陶瓷涂料的热喷涂技术及其工艺特点,分析了全新的陶瓷涂料及纳米陶瓷涂料的性能,研究了热喷涂工艺种类、特性和适用范围,同时指出了陶瓷热喷涂技术在汽车上的应用前景。     

Heat treatment of nanostructured thermal barrier coating

A nanostructured thermal barrier coating has been prepared by air plasma spraying using YSZ (8 wt% Y₂O₃ partially stabilized zirconia) nano powder. The effect of annealing on the nanostructured zirconia coating has been investigated. The grain size of the nanostructured zirconia coating increased with increasing annealing time and temperature. Grains grew with preferential direction and into a columnar structure. The growth activation energy in the nanocrystalline grains is very low, which comes from existence of micro-pores in the coating and the grain-rotation-induced grain coalescence (GRIGC) mechanism.     

Investigation of the thermomechanical properties of a plasma-sprayed nanostructured zirconia coating

Yttria partially stabilized nanostructured zirconia coatings were deposited by atmospherical plasma spraying (APS). The microstructure of the as-sprayed nanostructured coating was characterized with Scanning electronic microscopy (SEM), Transmission electron microscopy (TEM), X-ray diffraction (XRD) and Raman spectrum (RS). The laser-flash diffusivity method and push-rod method were used to examine the thermomechanical properties of the nanostructured zirconia coatings. The results obtained indicated that the plasma-sprayed zirconia coating possessed nano-structure and its average grain size was about 73 nm. The average thermal expansion coefficients of the nanostructured coating at the first thermal cycle and second thermal cycle from room temperature to 1200 °C are 11.0 and 11.6×10⁻⁶ °C⁻¹, respectively. The thermal diffusivity of the nanostructured zirconia coating was 1.80–2.54×10⁻³ cm²/s between 200 and 1200 °C. The microhardness of the nanostructured zirconia coating was 8.6 GPa, which was 1.6 times as large as that of traditional zirconia coating.     

Comparison of thermal shock resistances of plasma-sprayed nanostructured and conventional yttria stabilized zirconia thermal barrier coatings

The main goal of the current study is evaluation and comparison of thermal shock behavior of plasma-sprayed nanostructured and conventional yttria stabilized zirconia (YSZ) thermal barrier coatings (TBCs). To this end, the nanostructured and conventional YSZ coatings were deposited by atmospheric plasma spraying (APS) on NiCoCrAlY-coated Inconel 738LC substrates. The thermal shock test was administered by quenching the samples in cold water of temperature 20–25 °C from 950 °C. In order to characterize elastic modulus of plasma-sprayed coatings, the Knoop indentation method was employed. Microstructural evaluation, elemental analysis, and phase analysis were performed using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and X-ray diffractometry (XRD) respectively. The results revealed that failures of both nanostructured and conventional TBCs were due to the spallation of ceramic top coat. Thermal stresses caused by mismatch of thermal expansion coefficients between the ceramic top coat and the underlying metallic components were recognized as the major factor of TBC failure. However, the nanostructured TBC, due to bimodal unique microstructure, presented an average thermal cycling lifetime that was approximately 1.5 times higher than that of the conventional TBC.     

纳米复合陶瓷涂层研究现状

介绍了国内外纳米复合陶瓷涂层的性能以及各种喷涂技术制备纳米陶瓷涂层的研究现状。与传统涂层相比,纳米涂层在韧性,强度和耐磨等性能均有了很大的提高。分析了面临的主要问题,并提出了相应的解决办法。     

Microstructure analyses and thermophysical properties of nanostructured thermal barrier coatings

Nanostructured 8 wt% yttria partially stabilized zirconia coatings were deposited by air plasma spraying. Transmission electron microscopy, scanning electron microscopy, and X-ray diffraction were carried out to analyze the as-sprayed coatings and powders. Mercury intrusion porosimetry was applied to analyze the pore size distribution. Laser flash technique and differential scanning calorimetry were used to examine the thermophysical properties of the nanostructured coatings. The results demonstrate that the as-sprayed nanostructured zirconia coatings consist of the nonequilibrium tetragonal phase. The microstructure of the nanostructured coatings includes the initial nanostructure of powder and columnar grains. Moreover, micron-sized equiaxed grains were also exhibited in the nanostructured coatings. Their evolution mechanisms are discussed. The as-sprayed nanostructured zirconia coating shows a bimodal pore size distribution, and has a lower value of thermal conductivity than the conventional coating.     

纳米结构材料

本文从微观结构、制备方法、性能及应用等方面介绍了纳米结构材料,特别是纳米陶瓷材料,并总结了纳米结构材料当前研究的特点及发展趋势.由于纳米结构材料具有与传统材料不同的性能,有着广泛的应用前景,将继续成为材料领域的研究热点.