高速电弧喷涂FeAlNbB非晶纳米晶涂层的组织与性能

为了提高钢铁材料的耐磨性和硬度,利用高速电弧喷涂技术在45钢基体上制备了FeAlNbB非晶纳米晶涂层.采用扫描电镜(SEM)、能谱分析仪(EDAX),透射电镜(TEM)和X射线衍射仪等设备对涂层的组织结构和相组成进行了分析,研究了非晶纳米晶的形成机制.实验结果表明:FeAlNbB非晶纳米晶涂层是非晶相、α-Fe、FeAl纳米晶和Fe3Al微晶共存的多相组织,涂层中非晶相含量约36.2%,纳米晶尺寸约14.1 nm;涂层组织均匀,结构致密,平均孔隙率约2.3%;非晶纳米晶涂层具有较高的硬度,其耐磨性是相同实验条件下制备的3Cr13涂层的2.2倍.     

电弧喷涂TiB_2陶瓷涂层Ni含量对其耐磨粒磨损性能的影响

采用TiB2和Al2O3的复合粉末作为粉芯,由低碳钢带包覆制成粉芯线材.通过电弧喷涂工艺制备成含TiB2陶瓷的涂层.采用湿砂橡胶轮磨损试验机对涂层的磨粒磨损性能进行了测试.研究了在粉芯中添加Ni元素后涂层中相组织的变化以及不同的Ni含量对涂层抗磨粒磨损性能的影响.通过XRD、SEM等分析方法研究了涂层磨粒磨损机理.结果表明,所制得的涂层有着优异的抗磨粒磨损性能,且Ni元素对于涂层的抗磨损性能有着重要的改善作用.     

电弧喷涂粉芯丝材的研究进展与应用

简述了电弧喷涂粉芯丝材的优点及制作工艺,介绍了电弧喷涂粉芯丝材的发展历程,以及耐磨损、耐腐蚀、耐高温电弧喷涂粉芯丝材的最新研究进展,展望了电弧喷涂粉芯丝材的应用前景,指出了金属陶瓷复合粉芯丝材、非晶态粉芯丝材、纳米粉芯丝材是未来电弧喷涂粉芯丝材的发展方向。     

高速电弧喷涂Fe-Al/Cr3C2涂层高温性能研究

使用高速电弧喷涂技术结合Fe-Al/Cr3C2粉芯丝材制备了铁铝金属间化合物涂层,对涂层的高温磨损性能、高温冲蚀性能和高温腐蚀性能进行了研究.结果表明,与基体比较,涂层的耐高温冲蚀性能良好,温度升高,涂层冲蚀性能提高,角度增大,冲蚀性能提高;由于Cr2O3的存在以及涂层结合能的提高,Fe-Al/Cr3C2涂层的高温抗腐蚀性能较高;由于C元素的富积,涂层具有优异的常温耐磨损性能,其高温耐磨损性能也较高.     

电弧喷涂含TiB2金属陶瓷复合涂层的性能

为了减少磨损给生产所带来的经济损失,利用电弧喷涂含TiB2的粉芯线材来制备含TiB2陶瓷的涂层,并对涂层的结合强度、硬度、抗热震性和耐磨粒磨损性能等进行了测试,利用金相显微镜、X-射线衍射仪、扫描电子显微镜等对涂层进行测试分析,研究涂层磨损机理.研究结果表明,涂层结合强度达到49MPa,显微硬度达887HV,具有良好的抗热震性能,耐磨粒磨损性能比基体Q235钢提高了4.5倍.研制的涂层具有极大的实际应用和推广价值.     

微束等离子喷涂Al2O3陶瓷涂层特性

采用轴向中心送粉式微束等离子喷涂系统在2kW级的小功率条件下制备了Al2O3陶瓷涂层.研究了电弧功率、工作气体流量和喷涂距离对粒子速度与涂层组织结构和性能的影响.采用光学显微镜观察涂层的组织结构,采用X射线衍射分析涂层的相结构,采用磨粒磨损质量损失表征涂层的性能,用热辐射粒子速度温度测量系统测试工艺参数对喷涂粒子速度的影响.结果表明,电弧功率、工作气体流量和喷涂距离对粒子速度的影响都比较明显,粒子速度随着电弧功率和工作气体流量的增加而增加,随着喷涂距离的增加而下降.涂层的磨粒磨损质量损失随电弧功率的增加而减少,而随工作气体流量和喷涂距离的增加而增加.分析表明粒子的温度对涂层磨粒磨损质量损失有较大的影响.采用微束等离子喷涂可以制备磨粒磨损性能与传统等离子喷涂在38kW下制备的涂层相当的Al2O3涂层.     

超音速电弧喷涂高温防护涂层的研究进展

综述了超音速电弧喷涂高温防护涂层的研究进展,介绍了涂层的种类、制备方法,展望了高温防护涂层的发展趋势。着重阐述了超音速电弧喷涂防护涂层的抗高温氧化性能,研究和优化新型喷涂丝材与涂层的化学成分、组织,提高涂层的组织结构稳定性和使用性能,促进高温防护涂层的发展。     

Ti-Al双丝超音速电弧喷涂涂层的滑动磨损特性研究

为了提高铝合金(LY12)的表面耐磨性,采用钛、铝金属丝材和SAS-Ⅰ型超音速电弧喷涂设备,利用二次回归正交试验方法、有润滑滑动磨损试验、涂层显微组织和磨损表面形貌观察、XRD分析,定量分析了喷涂电压和喷涂距离对涂层滑动磨损体积的影响规律,并进行了喷涂工艺参数的优化及其与基体滑动磨损的对比试验.结果表明:在特定的磨损和喷涂条件下,当喷涂距离较小时,随喷涂电压的增大,涂层的体积磨损量逐渐减小;随着喷涂距离的增加,涂层的体积磨损量随喷涂电压的升高逐渐增大,并且喷涂距离越大,涂层的体积磨损量随喷涂电压增大的速率愈大.当喷涂电压比较低时,涂层的体积磨损量随喷涂距离的增大而降低,但是,随喷涂电压的逐渐升高,涂层的体积磨损量随喷涂距离的增大逐渐上升,并且,喷涂电压愈高,其随喷涂距离而增加的速率越快.当喷涂电压和喷涂距离分别为26V和0 236m时,涂层具有最佳的耐滑动磨损性能,根据该工艺参数制成的涂层,其滑动磨损体积仅为LY12铝合金的1/38.84.即在适当的工艺条件下,Ti-Al双丝超音速电弧喷涂涂层对LY12铝合金具有显著的表面耐磨强化作用.     

Structure and mechanical properties of Ti-Al-Si-N protective coatings deposited from separated plasma of a vacuum arc

Protective coatings of the Ti-Al-Si-N system have been deposited from vacuum arc by sputtering a cathode of composition 78Ti-16Al-6Si in nitrogen. The coatings of the Ti-Al-Si-N system have been studied using X-ray diffraction analysis to examine phase compositions and substructure, atomic force microscopy to analyze the topography, X-ray fluorescence to define the chemical composition, and nanoindentation to measure hardness and elastic modulus. It has been found that as the nitrogen pressure in the deposition chamber increases, in the Ti-Al-Si-N system the transition from nanocrystalline (to 0.04 Pa) to nanocomposite (0.04–0.66 Pa) and X-ray amorphous (0.66–1.1 Pa) coatings takes place, and at a pressure of 2.7 Pa, the amount of the crystalline phase abruptly increases again. The highest mechanical characteristics and thermal stability have been shown by a coating having the nanocrystalline structure and nanocomposite coatings with a low content of amorphous phase, whose hardness attains 47 GPa.     

超音速电弧喷涂Ti-Al涂层抗滑动磨损性能研究

采用二次正交回归试验设计原理和钛铝双丝超音速电弧喷涂Ti-Al合金复合涂层方法，对LY12铝合金进行了表面强化研究，并采用金相、XRD、SEM、硬度和磨损试验方法，对涂层的组织结构及力学性能进行了表征，考察了喷涂工艺参数对涂层孔隙率、显微硬度和耐滑动磨损性能的影响，研究结果表明：在本文的实验条件下，涂层的体积磨损量、孔隙率、显微硬度与喷涂电压和喷涂距离之间的变化规律，可用回归模型进行描述；随喷涂电压的增大，涂层磨损量逐渐下降；喷涂距离小于220mm时，随喷涂距离的增大涂层磨损量逐渐增大；喷涂距离为220mm时，磨损量达到最大，继续增加喷涂距离，涂层的磨损量逐渐下降；在干摩擦条件下，Ti-Al合金涂层的磨损机制主要以化合物相剥落引起的磨粒磨损和氧化磨损为主。     

超音速电弧与普通电弧喷涂FeCrNiB涂层的耐磨损性能

为了提高电弧喷涂涂层的结合强度及耐磨损性能,采用超音速电弧喷涂技术和普通电弧喷涂技术在Q235钢表面分别制备了Fe17Cr5NiB涂层,通过扫描电镜(SEM)、X射线衍射仪(XRD)、显微硬度计、摩擦磨损试验机等手段对比分析了2种涂层的微观结构及性能。结果表明:超音速电弧涂层具有更加致密的结构,其平均孔隙率为0.95%,远低于普通电弧涂层;超音速电弧涂层与基体呈紧密结合,其结合强度为60 MPa,而普通电弧涂层与基体之间呈明显的分层状态,其结合强度仅为28 MPa;超音速电弧涂层具有良好的非晶态结构及致密性,使其具有远高于普通电弧涂层的硬度以及耐磨损性能,显微硬度高出普通电弧涂层32.27%,耐磨损性能是普通电弧涂层的2倍以上(是基体的14倍以上)。     

Research on automatic high velocity arc spraying technique and metastable coating materials

Into the 21st century, remanufacturing engineering has been accepted by more and more people in China. Remanufacturing is an industrial maintenance
technology for worn or waste electro-mechanical products using advanced technology, which means the high-level stage for the maintenance and surface engineering. In this paper, a new automotive high velocity arc spraying system was introduced. And three kinds of advanced amorphous and nanocrystalline metastable coatings were developed, including Fe, Ni and Al-based amorphous and nanocrystalline composite coatings. Their research development and
applications were introduced. And the development trends of high velocity arc spraying system and advanced metastable surface protective coating materials on the remanufacturing engineering were indicated.     

Influence of multi-interfacial structure on mechanical and tribological properties of TiSiN/Ag multilayer coatings

The TiSiN/Ag multilayer coatings with bilayer periods of ~50, 65, 80, 115, 150, and 410 nm have been deposited on Ti6Al4 V alloy by arc ion plating. In order to improve the adhesion of the TiSiN/Ag multilayer coatings, TiN buffer layer was first deposited on titanium alloy. The multi-interfacial TiSiN/Ag layers possess alternating TiSiN and Ag layers. The TiSiN layers display a typical nanocrystalline/amorphous microstructure, with nanocrystalline TiN and amorphous Si₃N₄. TiN nanocrystallites embed in amorphous Si₃N₄ matrix exhibiting a fine-grained crystalline structure. The Ag layers exhibit ductile nanocrystalline metallic silver. The coatings appear to be a strong TiN (200)-preferred orientation for fiber texture growth. Moreover, the grain size of TiN decreases with the decrease of the bilayer periods. Evidence concluded from transmission electron microscopy revealed that multi-interfacial structures effectively limit continuous growth of single (200)-preferred orientation coarse columnar TiN crystals. The hardness of the coatings increases with the decreasing bilayer periods. Multi-interface can act as a lubricant, effectively hinder the cracks propagation and prevent aggressive seawater from permeating to substrate through the micro-pores to some extent, reducing the friction coefficient and wear rates. It was found that the TiSiN/Ag multilayer coating with a bilayer period of 50 nm shows an excellent wear resistance due to the fine grain size, high hardness, and silver-lubricated transfer films formed during wear tests.     

Lubrication mechanisms of C‐MoS2‐Fe2O3 (Fe3O4) nano‐composite lubricants at the rubbing interfaces of non‐copper coated solid wires against the contact tube

Graphite‐MoS₂‐Fe₂O₃ (Fe₃O₄) nano‐composite lubricating coatings were prepared on the surfaces of non‐copper coated solid wires by a mechanical coating technique. The tribological behaviours of graphite‐MoS₂‐Fe₂O₃ (Fe₃O₄) coatings at the rubbing interfaces of welding wires against the contact tube were investigated. The results demonstrate that the lubricating properties of graphite‐Fe₃O₄ coatings outperform the lubricating properties of graphite‐Fe₂O₃ coatings. The anti‐wear performance of the contact tube is strengthened with increasing nano‐MoS₂ contents. Layers of protective tribofilms are formed at the rubbing interfaces of welding wires against a contact tube by tribochemical reaction among lubricants. The tribofilms are composed of FeO, MoO₃ and FeMoO₄ with excellent lubricating properties. They can avoid direct contact of welding wires against the contact tube, thus decreasing contact tube wear. With the transition of the contact tube wear from mild to severe, the dominant wear mechanisms of contact tube change from fatigue peeling and oxidative wear to abrasive wear and arc ablation.     

Fabrication and evaluation of SixNy coatings for total joint replacements

Wear particles from the bearing surfaces of joint implants are one of the main limiting factors for total implant longevity. Si(3)N(4) is a potential wear resistant alternative for total joint replacements. In this study, Si(x)N(y)-coatings were deposited on cobalt chromium-discs and Si-wafers by a physical vapour deposition process. The tribological properties, as well as surface appearance, chemical composition, phase composition, structure and hardness of these coatings were analysed. The coatings were found to be amorphous or nanocrystalline, with a hardness and coefficient of friction against Si(3)N(4) similar to that found for bulk Si(3)N(4). The low wear rate of the coatings indicates that they have a potential as bearing surfaces of joint replacements. The adhesion to the substrates remains to be improved.     

镍铝复合丝和镍铝合金丝及其涂层

介绍了镍铝复合丝和镍铝合金丝及其涂层的成分、相结构 ,比较分析了涂层的结合强度 ,分析了涂层自结合作用机理 ,估算了喷涂一平方米面积所消耗的丝材及相应用丝材成本 ,介绍了两种材料适用的对象及设备     

Phase Stability in Nanostructures

Nanostructured materials provide access to tailor‐made materials properties by microstructural design. Excellent mechanical properties such as high strength or wear resistance are often found in nanocrystalline materials. For magnetic materials, the design of nanostructured composites offers advantages if the structural scales match the intrinsic magnetic length scales. In some cases, as in the new nanocrystalline soft magnetic alloys, the combination of amorphous and nanocrystalline phases is necessary to obtain the desired properties. This rises the question of the limiting size for a stable crystalline structure, especially in contact with an amorphous phase. These considerations, which have been of interest for basic research in the context of the microcrystalline model for amorphous materials, are of technical importance for the optimization of nanostructured composites. Recent model experiments about the stability of thin Fe‐based glass forming alloy films are reviewed. A relationship between phase stability, composition, and interface density has been established. The implications of the results for the design of nanostructured alloy systems are discussed.     

45钢表面超音速电弧喷涂Ti-Al涂层的组织与性能研究

采用自行开发研制的超音速电弧喷设备，在45钢表面制成了钛铝合金复合涂层。并利用金相显微镜、X射线衍射仪、扫描电镜、电子探针，对涂层的成分、相结构、显微组织及其结合强度、显微硬度进行了研究。结果表明，利用超音速电弧喷涂设备，可以在45钢表面形成 度高、孔隙率低，结合强度较好和硬度高的Ti-Al合金涂层。     

Surface Refinement of Metal Foams

Aluminium foams produced via the PM‐process are characterized by a moderate specific strength, a high surface roughness, and a poor wear behavior; to increase their mechanical properties and to improve the surface finish, wear and corrosion resistance; thermally sprayed coatings can be applied. The quality of the coating depends on the coating material, the chosen process, the preparation of the surface and spraying parameters. Aluminium alloys and iron based alloys for abrasive applications were deposited via electric arc spraying, ceramic coatings against wear were deposited by means of plasma spraying. Hard metallic coatings for severe abrasive applications were applied by high‐velocity‐oxyfuel spraying (HVOF). The results proved the suitability of this technique to significantly enhance the mechanical properties and the surface finish of metal foams. The specific strength and stiffness of the new composite materials outperform pure metal foams. The corrosion behavior was tested performing a salt spray test.     

反应等离子喷涂TiC/Fe涂层的摩擦磨损性能研究

采用等离子喷涂前驱体热分解技术制备的Fe-Ti-C系反应热喷涂粉末,在低碳钢基体上沉积TiC/Fe金属陶瓷复合涂层.利用SEM和X射线衍射仪对涂层的显微组织结构、磨损表面及其相组成进行分析;采用SRV型往复式摩擦磨损试验机评价喷涂涂层的摩擦磨损性能.结果表明: TiC理论含量为53%(质量分数)TiC/Fe金属陶瓷涂层的耐磨粒磨损性能较好,相比基体提高了约25倍;反应等离子喷涂TiC/Fe陶瓷涂层的磨损机制主要为粘着磨损和轻微的剥落.