推广应用热喷涂技术 修复、强化设备零件

新港船厂特种修理服务站是全国热喷涂协作组和中船总公司喷涂、电刷镀协作组的首批成员单位之一,1979年开始从事热喷涂和电刷镀的研究和推广应用工作,1983年基本形成了生产能力。为了扩大应用领域,1985年从美国METCO公司引进了等离子喷枪、火焰喷枪和电弧喷枪等13台套喷涂设备。为了提高人员的技术素质,我们聘请了天津等离子技术研究会、天津大学和美国METCO公司等单位的中外喷涂专家,来厂举办技术培训,全站人员都取得了天津等离子技术研究会和美国METCO公司的技术合格证书。     

对提高等离子喷枪的热焓和热效率因素的分析

一、前言等离子喷枪的热焓是直接影响到喷涂粉末的熔化效果和粉末的沉积效率。喷枪的热效率则是反映等离子电弧对工作气体加热的效果。它们都是衡量等离子喷枪性能的主要指标。因此,研究和分析影响等离子喷枪的热焓和热效率等诸因素对于提高等离子喷枪的性能、涂层质量、喷涂效率和节省能源等方面,均具有很现实的意义。     

PLC在等离子喷涂控制中的应用

等离子喷涂作为一种应用广泛的热喷涂工艺，几十年来在我国发展迅速。作为喷涂工艺的保障，等离子喷涂设备也得到了长足的发展。在等离子喷涂设备中，控制系统起的作用至关重要，它起着控制喷涂过程、喷涂参数、遇异常情况保护电源和喷枪不被烧毁等作用。     

对提高等离子喷枪的热焓和热效率因素的分析

<正> 一、前言等离子喷枪的热焓是直接影响到喷涂粉末的熔化效果和粉末的沉积效率。喷枪的热效率则是反映等离子电弧对工作气体加热的效果。它们都是衡量等离子喷枪性能的主要指标。因此,研究和分析影响等离子喷枪的热焓和热效率等诸因素对于提高等离子喷枪     

勇于攀登的战士——记等离子喷枪研制者王海军

这里介绍的是一位普通战士,他研制成功的78WⅡ型等离子喷枪,使等离子喷涂技术在我国的应用推进了一步。1986年,他应清华大学的邀请,参加了“七五”攻关项目大功率等离子陶瓷喷枪的研制。1988年5月,他撰写的《Ⅱ型等离子喷枪的研制和设计原理》学术论文在全国热喷涂学术研讨会上获一等奖。这位战士就是北京部队某坦克修理大队自学成才的王海军。     

油漆喷枪的研究现状

随着油漆喷涂技术的不断发展和广泛应用,作为该技术核心装置的油漆喷涂喷枪日益受到关注,改进现有的油漆喷涂装置和研发新装置,对获得高质量的涂层和提高喷涂效率、降低成本十分重要。文章综述了各类油漆喷涂喷枪的原理、特点、结构和现有的几种雾化方式、现有喷枪的优势以及喷枪所存在的一些问题,并列举了关于喷枪喷嘴、寿命和雾化效果方面不断优化的研究实例,并据此提出了现有的油漆喷涂喷枪还应继续优化以满足喷涂技术不断发展需要的建议。     

等离子喷涂射流的三维非稳态数值模拟

基于局域热力学平衡假设,建立等离子喷涂射流的三维非稳态湍流模型,运用计算流体力学软件ANSYS CFX模拟了氩/氢等离子喷涂过程中等离子特性分布以及喷枪内部场变化对射流形态的影响,并与高速摄像机的拍摄结果进行了对比。结果表明:模拟得到的射流波动明显,其形态与试验得到的结果吻合较好;喷枪内与射流域等离子体特性分布表现出明显的三维特征,其中速度分布的三维特征较之温度的更加明显;射流射入大气中后,温度和速度均沿轴向衰减,随着射流发展,与冷空气的卷吸作用愈明显,等离子体与冷空气之间能量和动量交换愈剧烈,大约距离喷枪出口27.4mm处其温度和速度的衰减加剧;射流域速度分布较之温度分布受空气影响更大。     

BT—G3型长寿命等离子喷枪的研制

等离子喷涂是利用电弧等离子体高温焰流将粉末熔化,并以一定的速度将熔化或热软化的粉末喷射到工件表面而形成涂层的一种工艺方法。喷枪是等离子体发生器,其性能的好坏直接关系到涂层的质量、喷涂成本以及整台等离子喷涂设备的性能,是等离子喷涂设备最关键的部件。 等离子喷涂常用的工作气体主要为Ar或N_2气,为了改善焰流的焓值和气氛,一般还需加少量的N_2或He气。因He气是稀有气体,价格极其昂贵,国内     

高效能超音速等离子喷涂技术的研究与开发应用

根据“高效能、超音速”等离子喷涂枪的设计指导思想，对超音速等离子喷涂枪的枪体、水路、气路、阴阳极结构及送粉结构进行了全新设计，利用等离子体物理学、流体力学和工程热力学的理论设计了独特的单阳极Laval喷嘴。通过对该喷涂枪和制备的涂层性能测试研究表明，该喷涂枪实现了低功率（＜80kW）、小气体流量（＜6m^3/h)条件下的高效能超音速等离子喷涂，在有效喷涂距离内的粒子飞行速度达450m/s。喷枪的主要性能指标：焰流速度、粉末沉积效率、涂层与能耗比、电极的性价比均达到或超过了美国TAFA公司的PlazJet高能高速等离子喷涂枪。制造陶瓷涂层的结合强度、孔隙率、显微硬度等性能明显优于METCO.9M普通等离子喷，但运行成本仅为国外超音速PlazJet等离子喷涂的一半。高效能超音速等离子喷涂技术在工业、国防、航空的功能领域具有广阔的应用前景。     

等离子喷涂技术研究与发展现状

本文从等离子喷涂设备、新型功能涂层、与等离子喷涂相关的测量技术等几个方面,综述了等离子喷涂技术的研究与发展现状。     

The erosion and abrasion characteristics of alumina coatings plasma sprayed under different spraying conditions

A series of plasma sprayed alumina coatings was evaluated regarding their erosion and abrasion characteristics. The coatings were deposited under different spraying conditions, using a commercial axial injection plasma spray system, and with powders of different grit sizes and crystallinity. A sintered bulk alumina and a conventionally sprayed coating, produced by a radial injection air plasma spray technique, were tested as reference materials. To evaluate the importance of energy input the coatings were produced using two different torch nozzle sizes and gas mixtures with a varied amount of hydrogen. The erosion and abrasion results indicate that hydrogen concentration, nozzle size and precursor powder type and size influence the tribological characteristics of the coatings. The wear resistance of the coatings seems to benefit from an increase in hydrogen concentration or torch nozzle size. The effect of precursor powder size on the wear resistance was more complex but indicates that sapphire powders of medium precursor sizes are advantageous to ordinary plasma spraying powders of alumina.     

Modelling and diagnostics of multiple cathodes plasma torch system for plasma spraying

Usage of a multiple-arcs system has significantly improved process stability and coating properties in air plasma spraying. However, there are still demands on understanding and controlling the physical process to determine process conditions for reproducible coating quality and homogeneity of coating microstructure. The main goal of this work is the application of numerical simulation for the prediction of the temperature profiles at the torch outlet for real process conditions. Behaviour of the gas flow and electric arcs were described in a three-dimensional numerical model. The calculated results showed the characteristic triangular temperature distribution at the torch nozzle outlet caused by three electric arcs. These results were compared with experimentally determined temperature distributions, which were obtained with specially developed computed tomography equipment for reconstructing the emissivity and temperature distribution of the plasma jet close to the torch exit. The calculated results related to temperature values and contours were verified for the most process parameters with experimental ones.     

超音速火焰喷涂在板式热交换器中的应用

对超音速火焰喷涂技术在板式热交换器中应用的可行性进行分析,确定了喷涂材料的选择依据和喷涂后应进行的性能指标试验,对比分析了喷涂后的优势,为该技术在板式热交换器中的推广应用提供参考与依据。     

等离子喷涂用纳米结构喂料的制备研究

探索了等离子喷涂用纳米结构喂料的制备工艺，并采用此方法制备了纳米结构的Al2O3-13％TiO2喂料。采用等离子喷涂工艺进行了喷涂试验。试验结果表明，该喂料可用于等离子喷涂，涂层良好。     

Investigations of some aspects of the spray process in a single wire arc plasma spray system using high speed camera

A high speed camera has been used to record and analyze the evolution as well as particle behavior in a single wire arc plasma spray torch. Commercially available systems (spray watch, DPV 2000, etc.) focus onto a small area in the spray jet. They are not designed for tracking a single particle from the torch to the substrate. Using high speed camera, individual particles were tracked and their velocities were measured at various distances from the spray torch. Particle velocity information at different distances from the nozzle of the torch is very important to decide correct substrate position for the good quality of coating. The analysis of the images has revealed the details of the process of arc attachment to wire, melting of the wire, and detachment of the molten mass from the tip. Images of the wire and the arc have been recorded for different wire feed rates, gas flow rates, and torch powers, to determine compatible wire feed rates. High speed imaging of particle trajectories has been used for particle velocity determination using time of flight method. It was observed that the ripple in the power supply of the torch leads to large variation of instantaneous power fed to the torch. This affects the velocity of the spray particles generated at different times within one cycle of the ripple. It is shown that the velocity of a spray particle depends on the instantaneous torch power at the time of its generation. This correlation was established by experimental evidence in this paper. Once the particles leave the plasma jet, their forward speeds were found to be more or less invariant beyond 40 mm up to 500 mm from the nozzle exit.     

等离子喷涂在先进材料研究与开发中的应用(二)──等离子制粉、植入与辅助沉积薄膜

等离子喷涂由于具有高洁净气氛、高热焓、高反应速度、高冷却速度、原位快速团结成形及中间环节少等特点，在先进材料研究与开发及现代成形制造技术中的应用越来越多。该文综述了等离子喷涂技术在等离子喷涂涂层、等离子近净成形、等离子合成高附加值材料、等离子制备超细微粉、等离子植入和等离子辅助沉积薄膜等方面特别是在等离子喷涂FGMs和等离子辅助沉积金刚石薄膜中的应用。     

几种新型热喷涂技术

论述了几种新型热喷涂的原理,以及热喷涂材料的新进展和热喷涂层质量监控的一些新方法,在此基础上介绍了热喷涂技术的最新应用.     

Characterisation of a microwave induced plasma torch for glass surface modification

Microwave induced plasma torches find wide applications in material and chemical analysis. Investigation of a coaxial electrode microwave induced plasma (CE–MIP) torch is conducted in this study, making it available for glass surface modification and polishing. A dedicated nozzle is designed to inject secondary gases into the main plasma jet. This study details the adaptation of a characterisation process for CE–MIP technology. Microwave spectrum analysis is used to create a polar plot of the microwave energy being emitted from the coaxial electrode, where the microwave energy couples with the gas to generate the plasma jet. Optical emission spectroscopy analysis is also employed to create spatial maps of the photonic intensity distribution within the plasma jet when different additional gases are injected into it. The CE–MIP torch is experimentally tested for surface energy modification on glass where it creates a super-hydrophilic surface.     

陶瓷涂布刮刀的研制

本文使用等离子喷涂工艺利用普通蓝钢刮刀制备陶瓷涂布刮刀.研究了涂层的微观结构,进行了涂层结合强度、耐磨性性能测试.在本文研究的参数变化范围内,以刮刀涂层平面度为评价标准,通过对电孤电流、走枪速度、喷涂距离三个喷涂工艺参数的正交设计试验,确定了最优等离子喷涂工艺参数.     

等离子喷涂技术在油膜轴承密封件上的应用

在介绍等离子喷涂技术和主要工艺参数的基础上,分析了油膜轴承密封件使用等离子喷涂的优势,并对比了油膜轴承密封件常用陶瓷涂层的喷涂参数与性能.