火焰喷塑涂层的防腐性能研究

作者利用FSP-2型火焰喷塑枪在A3钢基体上喷涂了高压低密的聚乙烯粉末涂层和环氧树腊粉末涂层。对涂层表面的通针孔进行了检测，并对这两种涂层进行了1032h的中性盐雾试验研究．这些试验的结果表明:火焰喷涂的聚乙烯和环氧树脂粉末涂层致密性较高，对基体有很好的保护作角，并且其防腐效果随着预处理工艺和喷涂厚度的不同而有较大的不同。     

火焰塑料粉末喷涂和喷涂层机械性能研究

本文阐述了火焰塑料粉末喷涂的原理、设备，应用自制设备探讨了火焰塑科粉末喷涂的工艺和涂层性能。研究认为，尼龙1010和PE聚乙烯塑料喷涂层具有优良的耐多种介质腐蚀的特点。     

表面喷涂对不锈钢零件耐磨性能的影响

在不锈钢表面采用超音速火焰喷涂了WC-10Co-4Cr涂层,并对喷涂粉末和涂层的显微形貌、物相组成进行了表征,研究了基体与涂层的耐磨性能。结果表明,不锈钢表面涂层与基体以机械结合为主、冶金结合为辅,基体与涂层间过渡良好,未发现气孔或者微裂纹缺陷;原始喷涂粉末的物相组成为WC、Co和少量Co3W3C相,经过超音速火焰喷涂处理后,涂层的物相组成为WC、Co6W6C和W2C相;经过超音速火焰喷涂处理后,涂层的摩擦磨损性能明显优于不锈钢基体,这主要与致密的涂层硬度较高、抗摩擦磨损能力更强有关。     

超音速火焰喷涂WC/Co涂层的组织性能研究

分析比较了等离子喷涂、超音速火焰喷涂的WC／Co涂层的形貌、显微组织、孔隙率、硬度、结合强度及其耐磨性。结果表明：超音速火焰喷涂涂层具有与粉末相近的相结构，与等离子喷涂相比涂层具有高的致密度、硬度和良好的耐磨性，涂层与基体结合情况也得到很大的改善。     

钢管涂塑方法——火焰喷涂法——《钢管涂塑技术》(14)

０概述火焰喷涂塑料粉末技术是一种适用于材料表面防护，表面强化和表面装饰的技术，它是在各种固体工程材料表面喷涂普通塑料或工程塑料粉末，用于制造基体与表层性能各异的复合材料。此技术不受基体材质、结构和形状的限制，实施效率高，涂层与基体结合牢固，可制备各种功能涂层，应用范围很广。１火焰喷涂的原理、装置及工艺１．１喷涂原理塑粉火焰喷涂是利用氧－乙炔火焰，采取沸腾送粉的方法，通过特制的火焰喷枪，将塑粉加热到熔融状态，并喷射到待喷物表面，得到平整光滑的塑料涂层的一种工艺过程。如图１所示，塑粉经过火焰喷枪中心…     

以沥青为前驱体制备TiC/FeCrNi反应火焰喷涂复合涂层

以钛铁粉、CrFe粉、羰基镍粉和碳的前驱体（石油沥青）为原料,通过前驱体碳化复合技术制备了Ti-Fe-Cr-Ni-C反应喷涂复合粉末,并通过普通火焰喷涂成功地合成与沉积了TiC/FeCrNi复合涂层.采用XRD和SEM对喷涂粉末和涂层的相组成和显微结构进行了分析,同时对涂层耐磨性能进行了对比研究.研究结果表明：采用前驱体碳化复合技术制备的Ti-Fe-Cr-Ni-C反应喷涂复合粉末粒度均匀、无有害相生成;所制备的TiC/FeCrNi复合涂层由不同含量TiC颗粒分布于金属基体内部而形成的复合强化片层叠加而成,TiC颗粒呈纳米级;基体由（Fe,Cr）和Cr0.19Fe0.7Ni0.11两相组成;相同条件下,所获TiC/FeCrNi复合涂层磨损体积大约是常规火焰喷涂Ni60涂层的1/8.     

火焰塑料粉末喷涂和喷涂层机械性能研究

本文阐述了火焰塑料粉末喷涂的原邢、设备,应用自制设备探讨了火焰塑料粉末喷涂的工艺和涂层性能。研究认为,尼龙1010和PE聚乙烯塑料喷涂层具有优良的耐多种介质腐蚀的特点。     

AZ91D热化学反应热喷涂陶瓷涂层耐蚀性研究

在镁合金AZ91D表面使用火焰喷涂制备陶瓷涂层，陶瓷涂层粉末配方为Al2O3＋TiO2＋SiO2＋ZnO＋Al。在喷涂制备涂层过程中伴随热化学反应的进行，涂层X射线分析发现，涂层内有MgSiO4、MgAl2O4等新相生成。耐蚀性试验表明，涂层的耐酸性能比基体提高了4倍，耐盐性能提高了1倍。     

火焰喷涂碳化物涂层的耐磨性研究

对碳化物复合粉末热喷涂工艺和Ni基自熔合金粉末热喷焊工艺进行了研究，在低碳钢基体上分别采用氧-乙炔火焰喷涂Co包WC粉末、Ni包WC粉末，以及火焰喷焊Ni60、Ni60 20％WC自熔合金工艺获得耐磨合金涂层。研究了涂层的显微结构和相特征以及耐磨性。结果表明，在喷焊Ni60 20％WC粉末涂层的组织中，由于加入了WC粒子，有效改善了涂层的显微组织和性能，得到了喷焊质量和耐磨性俱佳的合金涂层。     

粉末结构对反应超音速喷涂涂层组织影响的热力学分析

利用团聚和非团聚Ti—C—Ni粉末在超音速火焰喷涂中分别得到含有不同成分的涂层。根据热力学原理，对团聚和非团聚Ti—C—Ni粉末在反应超音速火焰喷涂过程中的热力学进行分析。结果表明：非团聚粉末分散在火焰焰流中，主反应是Ti O2=TiO2；而团聚粉末在喷涂过程中能够满足发生自蔓延反应Ti C=TiC的条件，可以原位合成得到了含有TiC的涂层。试验结果表明：试验结果与热力学分析基本吻合。     

Metallic coating of aerospace carbon/epoxy composites by the pulsed gas dynamic spraying process

A method for applying metallic coatings to high fibre volume fraction aerospace carbon/epoxy polymer matrix composites is presented. The pulsed gas dynamic spraying process was used for depositing zinc coatings on composites featuring a thin layer of copper particles co-cured into the laminate. No surface preparation was required on the cured substrates prior to spraying hence no damage was induced in brittle carbon fibres. Polymer matrix composite substrates with an added layer of co-cured copper particles were manufactured using a standard autoclave process. External substrate heating was not required. Metal powder and epoxy degradation were avoided through low process temperatures. Satisfactory cohesive and adhesive characteristics, low porosities and good microhardness values were obtained for a range of coating parameters. Microhardness and porosity of coatings deposited on polymer matrix composites compared well with those of similar coatings deposited on metallic substrates.     

Effects of surface roughness,texture and polymer degradation on cathodic delamination of epoxy coated steel samples

The Scanning Kelvin Probe (SKP) technique was used to investigate the effects of surface roughness, texture and polymer degradation on cathodic delamination of epoxy coated steel. The cathodic delamination rate of the epoxy coatings dramatically decreased with increased surface roughness of the underlying steel substrate. The surface texture of the steel substrates also had a significant effect in that samples with parallel abrasion lines exhibiting faster cathodic delamination in the direction of the lines compared to the direction perpendicular to the lines. The cathodic delamination kinetics of epoxy coatings previously exposed to weathering conditions increased with prolonged exposure due to pronounced polymer degradation. SEM observation confirmed that the cyclic exposure to UV radiation and water condensation caused severe deterioration in the polymer structures with surface cracking and erosion. The SKP results clearly showed that the cathodic delamination of the epoxy coatings was significantly influenced by the surface features of the underlying steel substrates and the degradation of the coatings.     

Incorporation graphene into sprayed epoxy–polyamide coating on carbon steel: corrosion resistance properties

In this study, the graphene incorporated into epoxy–polyamide coatings were successfully obtained on carbon steel substrates by spraying process. The corrosion resistance properties of the coatings were investigated, including salt spray corrosion, sea water corrosion and electrochemical corrosion resistance. The results show that the addition of graphene could improve the corrosion resistance properties of the epoxy–polyamide coatings. The coatings in the presence of graphene had better salt spray corrosion than that in the absence of graphene. The surface of the epoxy–polyamide coating exhibited lots of pitting corrosion. The coatings with the addition of graphene showed better sea water corrosion than the coating without graphene. After drying, the epoxy–polyamide coating in the absence of graphene was broken and failed. The coating with 1?wt-% graphene exhibited the best anticorrosion capability as evidenced by the highest corrosion potential and the lowest corrosion current density. The graphene incorporated into epoxy–polyamide coatings were shown to effectively protect carbon steel against corrosion because the graphene nanosheets could be acted as the good chloride ions, oxygen and water molecules barrier.     

Reducing the water absorption in epoxy coatings by silane monomer incorporation

In this communication, 3-glycidoxypropyltrimethoxy silane (GPTMS) was used as an additive to inhibit the water absorption of epoxy coatings. Coating capacitance, which was measured by electrochemical impedance spectroscopy (EIS), was employed to calculate the amount of water uptake in epoxy coatings in aqueous solution. The water absorption in epoxy coatings was found to decrease drastically after incorporated with silane component. It was interestingly found that the glass-transition temperature (T_g) of silane-mixed epoxy coatings continuously increased during the immersion, extremely contrast with that of silane-free polymeric substrates, which was observed to decrease significantly after water permeation as reported in previous literatures.     

Simultaneous determination of the coating thickness and its longitudinal velocity by ultrasonic nondestructive method

The ultrasonic reflection coefficient amplitude spectrum (URCAS) has been extended to obtain the coating thickness and its longitudinal velocity at the same time on thick substrates. A model was set up first to represent the ultrasonic waves reflected from a coating system at normal incident, and the expression of URCAS was derived in order to obtain the coating thickness and velocity. Then, an inverse algorithm based on the Gauss–Newton method was introduced to determine the thickness and velocity by comparing the theoretical and measured URCAS. Experimental validation was conducted on the homogeneous epoxy coatings on the aluminum substrates and inhomogeneous ZrO₂?7 wt%Y₂O₃ (YSZ) coatings on the superalloy substrates. The relative errors of the thickness and velocity measurement were in the ranges of 2.15–2.35% and 2.67–4.40% for epoxy coatings, and between 5.33–5.96% and 8.95–9.66% for YSZ coatings. It is concluded that the URCAS combined with inversion technique can be applied to obtain the thickness and longitudinal velocity of coatings simultaneously.     

Evaluation of nanosilicate filled poly (vinyl chloride-co-vinyl acetate) and epoxy coatings

The corrosion protection, mechanical and thermal properties of nanoclay filled epoxy and poly (vinyl chloride-co-vinyl acetate) (VYHH) resins have been studied. Nanoclay was incorporated into VYHH at 0%, 0.5% and 1.5%wt loadings, and into epoxy at 0% and 1.5% loadings. Steel substrates were prepared and coated with each of the prepared coatings. Some of the samples were submerged in a tank containing 5% NaCl solution and tested periodically using electrochemical impedance spectroscopy (EIS) to study the effect of the nanoclay on the corrosion protection of the coatings. Films were cast from each system to be used to evaluate the mechanical performance of the coatings. Notched and unnotched samples were cut from the films and some were submerged in the 5%NaCl solution while some were left unsubmerged as controlled samples. EIS measurements showed that VYHH/0.5%nanoclay provided superior barrier protection. The nanoclay filled epoxy exhibited increased barrier properties after 21 days. The tearing energy of the neat VYHH coating decrease by 27% after submersion, while the nano coatings showed a slight increase. The neat epoxy showed no change in the tearing energy after submersion, while that of the nano coating was increased by 14% after submersion. Differential scanning calorimetry (DSC) results showed that the nano coatings have improved the thermal barrier properties compared to the neat.     

管道外防腐涂层技术的发展与应用现状

本文介绍了管道外防腐涂层的基本要求、国内管道外防腐涂层的发展历程、以及管道外防腐涂层技术，包括：石油沥青、煤焦油瓷漆、聚乙烯胶带、环氧煤沥青、熔结环氧粉末（FBE）、聚乙烯防腐层（2PE／3PE）、双层熔结环氧粉末、100％固体含量聚氨酯／聚脲涂层等，并且分析了各种防腐涂层在工程中的应用情况和存在的问题，提出了一些改进意见。     

Formulation and evaluation of nano-structured polymeric coatings for corrosion protection

The effect of the addition of multi-walled carbon nano-tubes (MWCNT) to epoxy and vinyl chloride/vinyl acetate copolymer coatings on their ability to protect the substrates was studied. Coatings were formulated from these resins with and without MWCNT reinforcement. Steel substrates were prepared and coated with each formulated coating and submerged in 5% NaCl solution to study their corrosion resistance by means of Electrochemical Impedance Spectroscopy (EIS). In addition, thin films from these polymers, with and without nano-reinforcement, were cast. Dogbone specimens were cut in order to study their mechanical properties. Some of these specimens were immersed in the NaCl solution for two weeks in order to compare their mechanical properties with samples not exposed to salt water. Optical microscopy was used to capture the progress of sample corrosion. EIS measurements showed that the addition of MWCNTs to epoxy and vinyl chloride/vinyl acetate copolymer (VYHH) coatings increased their charge transfer resistance in comparison with the neat coatings. This is an indication of the enhanced corrosion protection of the nano-coatings. In addition, mechanical strength tests, both before and after immersion in 5% NaCl solution, showed that thin films from both epoxy and VYHH resins containing MWCNTs had improved strength, an indication of an improvement in the coatings' cohesive properties.     

长输管道防腐层优化设计及应用技术探讨

防腐层缺陷造成管道加速腐蚀,防腐设计是长输管道建设重要内容.分析环氧粉末、聚烯烃和三层聚乙烯防腐层的优缺点,总结3LPE防腐层在制管工艺、涂装工艺、管材缺陷、热收缩带补口、内涂层失效、弯管防腐和施工质量的技术现状和瓶颈问题.提出了长输管道防腐层选型和优化设计的原则要素,旨在提高管道安全管理水平、保障管道可靠运行.     

Improving the corrosion performance of epoxy coatings by chemical modification with silane monomers

In this communication, commercial epoxy resins were chemically modified with various silane monomers under the catalysis of organotin compound, aiming to enhance the corrosion resistance of epoxy coatings on 2024-T3 aluminum substrates. Immersion studies conducted in 3.5 wt.% NaCl solution showed that the coating capacitance (C_c) decreases significantly after the silane modification, as measured by electrochemical impedance spectroscopy (EIS), indicating the higher resistance to water permeation. EIS measurements also indicated an enhancement in protectiveness of silane-modified epoxy coatings against substrate corrosion, which was characterized by higher charge transfer resistances (R_ct) and lower double layer capacitance (C_dl) at substrate/electrolyte interface. The adhesion of epoxy coatings was also found to improve after the modification with silane components. The best performance was observed for coating system modified by 3-glycidoxypropyltrimethoxy silane (GPTMS).