等离子喷涂制备固体氧化物燃料电池电解质涂层研究进展EI北大核心CSCD

等离子喷涂作为一种高性价比的涂层沉积工艺,在固体氧化物燃料电池(SOFC)电解质制备方面比传统方式更灵活、高效,尤其在大面积电解质快速成形上,表现出良好的发展潜力。介绍SOFC的工作原理和研究趋势,综述电解质材料及等离子喷涂制备工艺的研究进展,指明等离子喷涂制备SOFC电解质涂层的发展方向。研究表明:氧化钇、氧化钪稳定的氧化锆是目前商业化应用最广泛的电解质材料,其他如氧化铈基及氧化铋基电解质还须解决还原气氛下价态变化问题,而镧锶镓镁氧化物和硅酸盐电解质则需解决成分和结构稳定性问题。在制备方面,传统湿化学法的高温烧结过程难以制备金属支撑型SOFC,磁控溅射和气相沉积等镀膜技术成本高、效率低,不适合电解质大规模生产。而等离子喷涂技术具有沉积效率高,对基体热输入小,可灵活调控涂层微观结构等优势。等离子喷涂SOFC电解质还存在较大探索空间,基于前期相关工作为后续中低温电解质制备及优化提供思路,随着电解质粉末成本下降及喷涂设备迭代升级,等离子喷涂技术有望在未来成为大规模高效制备SOFC电解质涂层的重要手段。     

Matlab图像处理在表征热喷涂涂层结构中的应用

基于Matlab的图像处理功能,提取了等离子喷涂Fe涂层中扁平粒子和氧化物的轮廓,并对等离子喷涂TiO2涂层的孔隙率进行了测量,其测量结果与直接称量法的测量结果进行了对比,结果表明采用Matlab的图像处理功能表征热喷涂涂层结构,其方法简单可行,测量涂层孔隙率结果稳定性好.     

高效能超音速等离子喷涂粒子特性及涂层特点

超音速等离子喷涂技术是热喷涂技术的关键技术之一.从基础及应用的角度,研究了高效能超音速等离子(HEPJet)喷涂粒子的特性,探讨了高效能超音速等离子在制备Ni/Al等金属及其合金涂层、WC-Co金属陶瓷涂层、ZrO2等氧化物陶瓷涂层上的特点.结果表明,高效能超音速等离子喷涂系统具有焰流温度高、射流速度快等特点;制备的涂层粒子变形充分,涂层均匀,孔隙率低,结合强度高,涂层质量好;可将适用于喷涂的所有粉末材料制备成高质量涂层.     

热喷涂汽车发动机气缸内壁涂层的研究进展

为了达到越来越苛刻的内燃机排放标准,减轻车身重量以降低燃油消耗是近年来车辆行业的重要发展方向之一。采用热喷涂方法在铝合金或铸铁气缸内壁喷涂减摩、耐磨并耐腐蚀的涂层代替传统铸铁缸套具有广阔的应用前景。首先介绍制备气缸内壁涂层的工艺流程,主要阐述现有制备气缸涂层的超音速火焰喷涂、电弧喷涂、大气等离子喷涂和等离子转移弧线材喷涂等工艺的原理,对不同热喷涂工艺特点进行了总结,阐明不同热喷涂方法获得的涂层结构特点。通过列举国内外车辆制造商先进热喷涂涂层的应用实例,进一步分析各类涂层的优缺点。最后提出优化喷涂参数、开发新型喷涂材料、控制涂层内应力和应对未来生物燃料是汽车气缸涂层的下一步研究方向。     

热喷涂纳米涂层20年回顾与展望

概述了热喷涂纳米涂层的发展,包括通过纳米粉体的再造粒技术形成热喷涂纳米结构涂层的过程,热喷涂纳米结构氧化铝/氧化钛耐磨抗蚀涂层材料的研发、产业化与成功应用,偶然获得热喷涂纳米自润滑涂层的过程,液料热喷涂纳米热障涂层的研发,新型热喷涂纳米热障涂层材料等。展望了热喷涂纳米涂层技术在国防和民用领域的应用前景,预计到2025年,全球热喷涂纳米涂层市场会达到65亿美元,其中20%左右的市场份额在中国。最后,指出通过对纳米粉体进行再造粒,在纳微观尺度上调控可喷涂粉体喂料的成分和组织结构,能够获得各种所需性能的纳米结构热喷涂涂层,可以用纳米材料制备出常规材料无法获得的全新高性能热喷涂纳米涂层,以满足各种高端装备关键构件的各种表面性能需求。所以,要通过政产学研用合作创新,加快纳米结构可喷涂粉体喂料产业化,发展高性能的热喷涂纳米涂层。     

超音速火焰喷涂（HVAF）Ni-WC合金涂层组织与显微硬度分析

0前言 20世纪90年代研制成功的超音速火焰喷涂（HVOF）技术是热喷涂领域一次革命性的进步,与等离子喷涂技术相比,HVOF可以大幅度提高热喷涂涂层的结合强度,并且同时减小甚至消除了涂层中的氧化物含量.     

焊接专利

一种制备具有生物活性的纳米氧化钛涂层的方法，一种高耐蚀耐磨等离子喷涂铁基非晶纳米晶涂层及制备方法，一种提高真空等离子喷涂碳化硼涂层结合强度的方法，一种固体氧化物燃料电池连接体的制备方法     

热喷涂制备固体氧化物燃料电池电解质层的研究进展

分析了固体氧化物燃料电池(SOFC)的发展趋势以及电解质的制备和特性对SOFC的工作温度及导电性的影响,并对SOFC电解质材料的研究现状进行了详细阐述。介绍了热喷涂技术在SOFC电解质材料制备中的技术优势,综述了热喷涂技术在SOFC电解质层材料制备中的应用,并对其进行了总结和展望。通过分析相关研究成果,认为降低工作温度必然成为未来SOFC研究的主要方向之一,而开发更多在中、低温下具有高电导率的电解质材料是未来研究工作的关键。应用最广泛的高温SOFC电解质材料是萤石结构的氧化钇稳定氧化锆,而钙钛矿结构的掺杂镁和锶的镓酸镧是最有前景的中、低温SOFC电解质材料。热喷涂技术具有基体材料不受限制、沉积速度快、灵活、成本低等一系列优点,在SOFC电解质涂层的制备中得到了广泛应用。对于高温SOFC电解质涂层可采用等离子喷涂辅助后处理工艺或直接优化其工艺,从而获得高致密、高电导率的电解质涂层,而中、低温电解质层的热喷涂制备方面的研究还有较大的拓展空间。     

热喷涂 Mo 及 Mo 基复合涂层研究进展

热喷涂Mo及Mo基复合涂层因熔点高、硬度高、耐磨损、耐腐蚀及高温性能稳定等诸多特点,而广泛应用于机械零件生产及表面修复。随着以资源有效利用和机械产品再制造为一体的可持续发展战略不断推进,此类涂层将拥有更为广阔的应用前景。首先介绍了国内外在热喷涂Mo及Mo基复合涂层方面的研究发展和应用现状;随后依据热喷涂技术的发展历程,分别总结论述了不同热喷涂技术,即火焰喷涂(普通火焰喷涂、高速火焰喷涂)、等离子喷涂(普通等离子喷涂、超音速等离子喷涂、微束等离子喷涂、低压等离子喷涂)及电热爆炸喷涂中,Mo及Mo基复合涂层的制备工艺、涂层性能特点及存在的问题;接着指出了热喷涂Mo及Mo基复合涂层在新概念武器、航空航天等高科技领域的应用前景。最后,就进一步拓展Mo及Mo基复合涂层在贫油减摩、高温高速耐磨、高温耐腐蚀及氧化等复杂环境下的应用范围,结合热喷涂技术的研究热点及发展方向,指出了未来热喷涂Mo及Mo基复合涂层在材料组分设计和工艺优化研究中应重点关注的方面。     

锅炉“四管”用耐磨耐蚀涂层研究进展

总结了锅炉"四管"失效的形式和机理.热腐蚀和高温冲蚀磨损是锅炉"四管"失效的主要原因,采用热喷涂金属涂层、陶瓷涂层及金属陶瓷复合涂层等可以有效控制热腐蚀和高温冲蚀磨损.目前制备高性能涂层常用的方法有等离子喷涂、电弧喷涂、超音速火焰喷涂等.详细介绍了高镍铬合金涂层的研究状况和喷涂工艺的特点,最后展望了纳米结构涂层在该领域的研究进展和应用前景.     

Fabrication and electrochemical performance of solid oxide fuel cell components by atmospheric and suspension plasma spray

The theory of functionally graded material (FGM) was applied in the fabrication process of PEN (Positive-Electrolyte-Negative), the core component of solid oxide fuel cell (SOFC). To enhance its electrochemical performance, the functionally graded PEN of planar SOFC was prepared by atmospheric plasma spray (APS). The cross-sectional SEM micrograph and element energy spectrum of the resultant PEN were analyzed. Its interface resistance was also compared with that without the graded layers to investigate the electrochemical performance enhanced by the functionally graded layers. Moreover, a new process, suspension plasma spray (SPS) was applied to preparing the SOFC electrolyte. Higher densification of the coating by SPS, 1.61%, is observed, which is helpful to effectively improve its electrical conductivity. The grain size of the electrolyte coating fabricated by SPS is also smaller than that by APS, which is more favourable to obtain the dense electrolyte coatings. To sum up, all mentioned above can prove that the hybrid process of APS and SPS could be a better approach to fabricate the PEN of SOFC stacks, in which APS is for porous electrodes and SPS for dense electrolyte.     

A comparative study of tribological behavior of plasma and D-gun sprayed coatings under different wear modes

In recent years, thermal sprayed protective coatings have gained widespread acceptance for a variety of industrial applications. A vast majority of these applications involve the use of thermal sprayed coatings to combat wear. While plasma spraying is the most versatile variant of all the thermal spray processes, the detonation gun (D-gun) coatings have been a novelty until recently because of their proprietary nature. The present study is aimed at comparing the tribological behavior of coatings deposited using the two above techniques by focusing on some popular coating materials that are widely adopted for wear resistant applications, namely, WC-12% Co, A1₂O₃, and Cr₃C₂-MCr. To enable a comprehensive comparison of the above indicated thermal spray techniques as well as coating materials, the deposited coatings were extensively characterized employing microstructural evaluation, microhardness measurements, and XRD analysis for phase constitution. The behavior of these coatings under different wear modes was also evaluated by determining their tribological performance when subjected to solid particle erosion tests, rubber wheel sand abrasion tests, and pin-on-disk sliding wear tests. The results from the above tests are discussed here. It is evident that the D-gun sprayed coatings consistently exhibit denser microstructures and higher hardness values than their plasma sprayed counterparts. The D-gun coatings are also found to unfailingly exhibit superior tribological performance superior to the corresponding plasma sprayed coatings in all wear tests. Among all the coating materials studied, D-gun sprayed WC-12%Co, in general, yields the best performance under different modes of wear, whereas plasma sprayed Al₂O₃ shows least wear resistance to every wear mode.     

提高等离子喷涂热障涂层隔热性能的方法

为进一步提高等离子喷涂热障涂层的隔热性能,对陶瓷材料的导热理论及热障涂层的热导率进行了研究.提出了包括寻求新型热障涂层陶瓷材料、添加掺杂剂、制备纳米涂层及双陶瓷层热障涂层等能够改善等离子喷涂涂层隔热性能的方法;并指出,采用等离子喷涂技术制备带颜色的稀土锆酸盐纳米双陶瓷层热障涂层,将会进一步改善热障涂层的隔热性能.     

石墨和C/C复合材料表面ZrB2-SiC陶瓷涂层的研究进展

C/C复合材料具有优异的高温力学性能,是航空航天领域最具发展前景的结构材料之一,但在高温含氧环境中的氧化问题严重地限制了其实际应用。涂层技术是提升基体抗氧化能力的有效手段,因ZrB_2-SiC陶瓷涂层具有优异的抗氧化、抗烧蚀、抗热震等性能,非常适合作为C/C复合材料的高温防护涂层。首先,介绍了ZrB_2-SiC陶瓷涂层在氧化和烧蚀过程中组织结构的演变规律,阐明了该涂层的高温防护机理;然后,综述了该涂层的主要制备方法(包埋法、CVD、等离子喷涂)及每种方法的优点与不足,并对不同方法所制备涂层的抗氧化性和抗烧蚀性进行了比较;之后,针对该涂层研究和应用中存在的问题,如涂层致密性差、元素分布不均匀、应用温度范围窄、与基体热匹配性差等,从粉体改性和掺杂改性两方面总结了该涂层的改性研究现状,重点阐述了对ZrB_2-SiC粉末进行喷雾造粒和感应等离子球化处理对于提升等离子喷涂涂层性能的重要意义;最后,从涂层制备、涂层结构设计、涂层改性、涂层性能测试等方面,指出了该涂层体系存在的主要问题和未来的发展方向。     

Adhesion improvements of Thermal Barrier Coatings with HVOF thermally sprayed bond coats

Thermal barrier coatings (TBC) are an effective engineering solution for the improvement of in service performance of gas turbines and diesel engine components. The quality and further performance of TBC, likewise all thermally sprayed coatings or any other kind of coating, is strongly dependent on the adhesion between the coating and the substrate as well as the adhesion (or cohesion) between the metallic bond coat and the ceramic top coat layer. The debonding of the ceramic layer or of the bond coat layer will lead to the collapse of the overall thermal barrier system. Though several possible problems can occur in coating application as residual stresses, local or net defects (like pores and cracks), one could say that a satisfactory adhesion is the first and intrinsic need for a good coating. The coating adhesion is also dependent on the pair substrate-coating materials, substrate cleaning and blasting, coating application process, coating application parameters and environmental conditions. In this work, the general characteristics and adhesion properties of thermal barrier coatings (TBCs) having bond coats applied using High Velocity Oxygen Fuel (HVOF) thermal spraying and plasma sprayed ceramic top coats are studied. By using HVOF technique to apply the bond coats, high adherence and high corrosion resistance are expected. Furthermore, due to the characteristics of the spraying process, compressive stresses should be induced to the substrate. The compressive stresses are opposed to the tensile stresses that are typical of coatings applied by plasma spraying and eventually cause delamination of the coating in operational conditions. The evaluation of properties includes the studies of morphology, microstructure, microhardness and adhesive/cohesive resistance. From the obtained results it can be said that the main failure location is in the bond coat/ceramic interface corresponding to the lowest adhesion values.     

Low conductivity plasma sprayed thermal barrier coating using hollow psz spheres: Correlation between thermophysical properties and microstructure

Life and thermal properties of plasma sprayed TBCs - widely used in gas turbine engines - are closely related to the microstructure of the ceramic top coating. Especially, the thermal behaviour of this coating is induced by the void shapes and networks which are in turn determined by both the spraying conditions and the feedstock material.A specific hollow yttria partially stabilised zirconia powder was produced in a one-step process by spray drying and an experimental statistical design study was conducted to investigate the influence of spraying variables (primary and secondary gas flow rates, arc current, spraying distance, spraying angle and traverse speed) on structure and properties of resulting plasma sprayed coatings. The coatings were characterized with respect to deposition efficiency, roughness, porosity and thermal conductivity. A reduction of 25% of the thermal conductivity was achieved by improving the spray and powder parameters. A quantitative characterization of the porous structure using image analysis of polished cross-sections was implemented. The parameters that have relevant influence on the coating porous structure were identified, and their relative importance was determined. An attempt was made to identify morphological criteria of the porous network (coarse/fine porosity ratio, cracks total length, cracks orientation) correlating with the thermal conductivity values.     

空心阴极电弧镀NiCrAlY涂层的抗氧化性能

采用空心阴极电弧离子镀技术制备NiCrAlY涂层,研究涂层的高温抗氧化性能。结果表明涂层组织致密,与合金结合状态良好。电弧离子镀NiCrAlY涂层在1 100℃恒温氧化100h后增重只有2.22mg/cm2,在100次循环氧化后仍没有失重现象,其抗恒温氧化和抗循环氧化性能远优于成分相近的超音速火焰喷涂、爆炸喷涂和大气等离子喷涂的NiCrAlY涂层。电弧离子镀NiCrAlY涂层在恒温氧化和循环氧化过程中表面均形成了连续致密、粘附性的氧化铝保护膜。氧化膜没有翘起和剥落现象,涂层组织在氧化后仍然完整致密。热喷涂NiCrAlY涂层在上述氧化过程中则生成了保护性较差的Ni、Cr和Al混合氧化物,并发生了氧化膜剥落,同时有严重的内氧化现象。     

等离子喷涂-物理气相沉积高温防护涂层研究进展

等离子喷涂-物理气相沉积（PS-PVD）是基于低压等离子喷涂发展起来的一种新型多功能薄膜及涂层制备技术。由于其独特的等离子射流特征,可实现气液固多相涂层沉积,获得非视线沉积。文中首先介绍了国内外PS-PVD技术等离子体数值模拟和在线检测技术的研究现状,其次讨论了PS-PVD羽-柱状结构热障涂层的形成机制及与传统热障涂层在热导率、抗冲蚀等性能方面的差异,阐述了PS-PVD技术制备环境障涂层的研究进展,最后对PS-PVD技术沉积高温防护涂层的优势和存在的问题进行了总结。