Nano SiC-Nickel Composite Coatings from a Sulfamat Bath Using Direct Current and Pulsed Direct Current

Composite plating is a method through which the fine particles of metallic or non-metallic compounds are co-deposited in a plated layer to improve surface properties such as lubrication, wear resistance, and corrosion resistance. In this study, nano-sized SiC particles were co-deposited with nickel from sulfamat bath using pulsed and direct currents. Scanning electron microscopy, microhardness, wear, and corrosion tests were carried out to characterize the coating properties. The results showed that microhardness, wear resistance, and corrosion resistance of Ni-SiC composite coatings increased compared to those of Ni films.     

Comparison of corrosion protective performance of nanostructured polyaniline and poly(1-naphthylamine)-based alkyd coatings on mild steel

Nanostructured materials have been establishing themselves as modern generation of high performance materials in many areas ranging from automotive engineering to bioengineering owing to a vast array of their unique properties. Improvements in environmental impact can also be achieved utilizing nanostructure particulates in coating and eliminating the requirement of toxic inhibitors such as chromates. The paper reports a comparative study on the corrosion resistance performance of soya oil alkyd containing nanostructured polyaniline (PANI) and poly(1-naphthylamine) (PNA) composite coatings. The corrosion protective performance was evaluated by physico-mechanical properties, corrosion rate, open circuit potential measurements, and SEM studies. The PNA/alkyd composite coatings were found to show far superior corrosion resistance performance as compared to PANI/alkyd system.     

耐蚀非金属材料在磷复肥生产装置中的应用

介绍了耐蚀非金属材料在磷复肥生产装置的应用，实践表明非金属材料在苛刻工艺条件下具有良好的耐蚀性能。     

ADVANCED QUALITY CONCEPTS AND COMPOSITE RELIABILITY THROUGH STATISTICAL PROCESS CONTROL

1.IntroductionTheproducti0nandtestingofcomp0sitematerialsinvolvesmanydifferentpr0cessstages,arangeofbaJsicingredientsandanumberoftestprocedures.Ifcomp0sitemateri-alsaret0perf0rmreliab1yinIowtemperatureapplicati0nsandmeettherequiredtechnicalandeconomicgoalsf0ruseinapplicationssuchassuperconductingmagnets,(fusi0nre-actors)0rascryogenstroagevesselsinspacecraft,itisessentialthattheirpr0pertiesbewellcharacterisedandrepr0ducible.StatisticalPr0cessContr0l(S.P.C.),isessentiallysupplementaryt0n0rmal…     

Corrosive Effect of Plastics,Rubber and Wood on Metals in Confined Spaces

Abstract

The corrosion of metals enclosed in equipment or packages is influenced by vapours arising from other materials which may also be present. Plastics, wood and rubber are the principal sources of such vapours. Even when no vapours are evolved, corrosion of a metal may result from contact with some non-metallic materials.

Samples of iron, zinc, copper, aluminium and cadmium either in contact with or in a sealed space with various types of non-metallic material, were exposed to corrosion. The extent of corrosion was observed and analyses were made of products and of the surrounding atmosphere. Formic and acetic acid are the most aggressive volatile products from wood and the same compounds, together with formaldehyde, ammonia and halogen acids, may be evolved from plastics and sulphur compounds from rubber. Of the plastics, phenolic resins, especially as mouldings filled with wood flour, and, of the woods, oak, chestnut and beech are the most likely to produce acetic and formic acid vapours, but other materials have appreciable specific vapour or contact effects.     

硫质量分数对船体钢诱发点蚀行为的影响研究

采用腐蚀浸泡的方法研究了酸性氯离子环境下S质量分数对低合金船板钢耐蚀性的影响,探讨了非金属夹杂物诱发点蚀形核的机理。结果表明,杂质元素S对钢的耐蚀性具有不利影响。随着S质量分数的增加,钢的耐点蚀性能恶化。S元素损害耐蚀性主要与钢中的非金属夹杂物有关。不同种类夹杂物诱发点蚀的机理有显著差异。单一MnS夹杂物与基体间存在缝隙,其诱导点蚀形核包括缝隙腐蚀和夹杂物溶解两个过程,MnS夹杂物是最敏感的点蚀诱发源;MXS-Al2O3复合夹杂物同样能诱发低合金钢的点蚀形核,包裹在Al2O3外层的硫化物优先发生溶解,成为腐蚀介质的通道,从而引发局部腐蚀。MnS-Al2O3夹杂物的点蚀形核能力大于CaS-Al2O3夹杂物,CaS遇到水容易发生水解并在夹杂物周边形成OH-,阻碍了坑内部的酸化,有利于抑制钢的耐局部腐蚀性能。     

Polymer coatings for biomedical applications: a review

This review surveys some of the recent literature concerning the use of polymer coatings for a variety of biomedical applications. These have been grouped into six broad categories: orthopaedic materials, cardiovascular stents, antibacterial surfaces, drug delivery, tissue engineering and biosensors. These, to some extent overlapping, sections have been ordered such that the literature generally progresses from polymer coatings on metallic to non-metallic substrates. Polymer coatings can bestow a wide range of functionalities due to their various properties, such as antiwear characteristics, mechanical strength, corrosion protection, electrical conductivity, biocompatibility and surface chemistry. The review period is from 2011 to the present (mid-2013).     

管道内防腐技术现状与研究进展

介绍了石油管道内溶解氧、二氧化碳、硫化氢、以及二氧化碳和硫化氢协同腐蚀的机理。综述了油气管道内防腐技术,现阶段主要的处理方式是选择耐蚀金属材料或非金属材料、添加缓蚀剂、涂层防腐和衬里防腐。分析了各种内防腐技术的优缺点,认为管道内防腐在未来的发展方向是将基材选择、添加缓蚀剂、内涂镀层和内衬里技术进行综合,以减缓管道内的腐蚀。低碳钢表面镀镍层自纳米合金化技术,即是集中内防腐技术的综合运用,得到了表面无缝冶金结合的高耐蚀性能管材,是未来发展趋势的代表。     

热处理对HA/Mg-Zn-Ca生物复合材料显微组织及性能的影响

采用剪切搅拌铸造结合热挤压工艺制备了1HA/Mg-3Zn-0.2Ca(质量分数,%)复合材料,研究了固溶及时效处理对挤压态1HA/Mg-3Zn-0.2Ca复合材料显微组织、力学性能及电化学腐蚀行为的影响。结果表明:挤压态复合材料经固溶处理(T4)后,第二相数量减少,晶粒尺寸增大,屈服强度降低,但延伸率和耐蚀性能有所提高。固溶超过3 h后,由于晶粒尺寸过分长大耐蚀能力又出现下降;固溶后时效处理(T6),复合材料屈服强度提高,耐蚀性变化不大。因此,对挤压态HA/Mg-Zn-Ca复合材料进行适当的固溶及时效处理可以提高复合材料的耐蚀性及延伸率。     

液态模锻SiCp/2A50力学性能及腐蚀行为研究

在研究2A50及SiCp/2A50复合材料力学性能的基础上,采用失重方法和电化学方法研究了2A50及SiCp/2A50复合材料在NaCl溶液中腐蚀行为和腐蚀机理,研究了不同尺寸、不同含量的增强颗粒SiCp对复合材料力学性能和腐蚀行为影响的变化规律。研究结果表明：当增强颗粒SiCp尺寸一定时,随着增强颗粒含量的增加,复合材料的强度增加,延伸率降低,而复合材料的腐蚀速率增加;当增强颗粒SiCp含量一定时,随着增强颗粒尺寸的增加,复合材料的强度降低,而延伸率则降幅较小,复合材料的腐蚀速率增加;复合材料中增强颗粒SiCp含量的变化并没有影响材料的腐蚀电位的变化,且与基体合金的腐蚀电位变化幅度较小;合金中的第二相与增强颗粒SiCp在复试过程中作为腐蚀阴极相,共同增加了合金的腐蚀速率;增强颗粒SiCp的加入降低了合金的耐蚀性能,且所研究的5种复合材料的腐蚀速率均大于基体合金的腐蚀速率。     

15 Jahre deutsche Korrosionforschung im Forschungsprogramm Korrosion der Deutschen Bundesrepublik — Teil II

15 Years of German corrosion research in the research programme corrosion of the Federal Republic of Germany — Part II The second part of this report (Pt. I se WuK 24 [1973] 6; 525–535) deals in particular with the possibilities of corrosion protection, and in particular inhibitors, electrochemical methods (cathodic protection), electrolytically deposited metal coatings (including the feasibility of influencing their properties by galvanizing conditons), sprayed and vacuum deposited coatings non-metallic inorganic coatings (passivating layers such as anodizing etc., as well as their preparation mechanisms) and organic coatings. A concluding part deals with test methods, on the one hand methods to test the corrosion behaviour of materials in various media and under various conditions on the other hand methods to test the efficiency of various corrosion protection methods. 434 ref.     

面向等离子体壁材料的腐蚀行为与涂层防护综述

面向等离子体材料(Plasma Facing Materials,PFMs)可保护磁约束核聚变装置部件,使此部件不受芯部边缘等离子体的影响,但等离子体与壁相互作用(Plasma-Wall Interactions,PWI)所引起的高温腐蚀、辐射损伤和燃料滞留等问题已然成为先进核聚变装置的发展瓶颈.目前,低Z材料(C、B...     

镁合金熔剂净化研究现状与展望

镁合金化学性质极其活泼，极易与氧、氮、水汽等发生化学作用，产生大量的非金属夹杂物和金属夹杂物，严重恶化了镁合金的铸造性能、力学性能及耐腐蚀性能。阐述了镁合金中的夹杂物来源及其危害，综述了镁合金净化熔剂的研究现状，并对熔剂的研究发展方向进行了展望。     

氧化物陶瓷阻氚涂层的研究进展

利用阻氚涂层(TPB)降低结构材料中的氚损失,是聚变堆发展中的热点研究之一。陶瓷具有低氚渗透性、耐腐蚀性、高硬度和高热稳定性等特性,是目前聚变堆阻氚涂层首选材料。相对于硅化物、钛基等非氧化物陶瓷材料,氧化物陶瓷涂层具有熔点高、化学性质稳定、耐腐蚀性和阻氚渗透因子(PRF)高等优势,因此针对氧化物陶瓷阻氚涂层的研究较多。主要综述了单一氧化物陶瓷、复合氧化物陶瓷阻氚涂层近年来的研究现状与发展,如Y2O3、Er2O3、Al2O3等及其复合氧化物陶瓷材料,其中,因Al2O3及其复合物涂层具有优异的阻氚性能,得到了广泛的关注和研究。重点阐述了制备工艺、基体效应和辐照等影响氧化物陶瓷涂层阻氚性能的因素及氚在材料中的渗透机制,并分析了当前阻氚涂层在材料制备以及模拟服役环境等方面存在的不足与今后的研究重点,指出了未来可能的氧化物陶瓷阻氚涂层,以期为阻氚涂层的研究与后续实验提供一定的方向。     

金属包装材料涂层防腐技术

金属材料在包装领域保持着极大的生命力,但化学稳定性较差、耐腐蚀性差是金属包装材料存在的主要问题,利用涂层技术在金属表面覆盖涂层是防止金属包装材料腐蚀的有效方法.在分析金属包装材料的性能及防腐蚀方法的基础上,结合金属包装材料腐蚀防护问题,对主要的金属涂层防腐技术及涂料涂层防腐技术进行了介绍.展望了金属包装材料涂层防护的应用发展情况及动态;指出了涂层隔离防护并不能从根本上解决金属材料的腐蚀问题,研发新型耐腐蚀材料成为涂层防护技术的发展方向.     

Korrosion in Alkalimetallkreisläufen. I. Mechanismen und Phänomene

Corrosion in alkalimetal circuits - I. Mechanisms and phenomena The corrosion of materials by liquid alkali metals is characterized by dissolution and deposition processes following a temperature gradient. Exchange reactions of oxygen and carbon or other non-metallic or metallic elements play important roles. Phenomena in technical systems with circulating melts of Li, Na, or K are discussed in terms of the mechanisms. Recommendations for the use and possible combinations of materials for alkali metal systems are given. The problems of corrosion and mass transfer are set into relation to questions of safety and operation of the systems. The corrosion problems can be solved by the selection of materials, by the construction of the components, and by the specification of the liquid alkali metal parameters.     

耐腐蚀氧化石墨烯复合涂层的研究进展

腐蚀问题会影响金属材料的安全性和耐久性,是造成工程装备和设施失效及破坏的主要原因,严重损害了经济发展和人身安全。涂层是最有效和经济的防腐措施,随着对涂层性能的要求越来越高,复合涂层材料受到科研工作者的广泛关注。石墨烯具有高导电率、高硬度和优异的阻隔性等性能,但同时具有疏水性和易团聚的特点。氧化石墨烯的结构与石墨烯相似,高长径比能够提供有效的阻隔性能,表面丰富的含氧基团为化学改性提供了反应位点,从而实现在基体中均匀分散的目的,是一种可用于增强涂层防腐能力的理想碳材料。首先介绍了氧化石墨烯的制备和化学改性方法,并且对比了不同化学改性方法的优缺点以及作用机制。然后分类阐述了氧化石墨烯复合防腐涂层的研究现状,探讨了氧化石墨烯含量、分散性和制备条件等因素对复合涂层的影响。最后从不同方面(制备工艺、分散技术、防腐机制和工程应用)分析了氧化石墨烯涂层存在的主要问题,并展望了氧化石墨烯涂层的发展方向。     

电沉积制备镍基复合镀层的研究进展

金属-陶瓷复合镀层可以显著改善的硬度、致密性、耐蚀性、耐磨性以及抗高温氧化性能等可显著得到改善,应用范围广泛。综述了影响复合镀层性能的几大因素,重点介绍了增强相粒子粒径、表面活性剂类型、制备镀层的沉积方式以及第二相颗粒种类对电沉积复合镀层性能的影响。陶瓷颗粒尺寸影响复合镀层的性能,细小颗粒对镍基复合镀层具有细晶强化作用,微米级陶瓷颗粒能够大大改善Ni基复合镀层的力学性能。超细纳米陶瓷颗粒作为增强相,可以显著提高复合镀层的耐蚀性,添加纳米颗粒的复合镀层的显微硬度优于添加微米颗粒复合镀层。非离子表面活性剂能提高第二相颗粒在镀层中的复合量及在镀液中的分散性,有利于获得高硬度的复合镀层,进而提高整个镀层的耐磨性和耐蚀性。超声波-脉冲电沉积法得到的复合镀层形貌更平整,晶粒更细小,结构更致密,且得到的复合镀层硬度更高,耐磨性、耐蚀性更好。与SiC复合镀层相比,SiO_2复合镀层具有更好的耐蚀性和抗氧化性。最后,分析展望了颗粒增强镍基复合材料的应用前景及未来研究的重点。     

轻水堆包壳锆材服役环境下延寿策略及研究进展

综述了核反应堆用锆合金的涂层研究现状。主要论述了非金属类涂层、金属类涂层以及MAX相涂层。其中MAX相既具有金属的性质,又具有陶瓷的性质。分析了包壳材料服役环境下的腐蚀行为,包括正常工况下的过热水氧化腐蚀和含锂离子的水溶液腐蚀行为,同时也关注了离子辐照行为以及事故工况下的高温蒸汽腐蚀行为。现有涂层材料普遍具有局限性,研究多侧重于高温蒸汽腐蚀。出现了一些新材料,比如可形成致密氧化膜的MAX相、硅涂层等,但是其正常工况下的应用前景不明。相比而言,金属类涂层在抗腐蚀方面更具优势,然而其抗辐照行为和中子经济性尚待研究。目前单一涂层技术在满足抗辐照和中子经济性的基础上尚不足以同时满足正常工况和高温蒸汽下的抗腐蚀性和高稳定性。组合涂层或者多层膜技术逐步受到重视。多元涂层氧化过程中的元素迁移动力学行为以及涂层基体界面的微合金化对结合力的影响具有深远意义,目前该方面的研究有待突破。     

Evolution of the impedance diagrams of 8090 Alloy in saline solution with low aggressiveness

Aircraft industry has focused in the search for new materials with high performance properties such as composite materials and aluminium alloys. During the last decade a new generation of aluminium-lithium alloys have been developed due to their low density and high elastic modulus. From corrosion viewpoint most of the work published on these alloys are based on atmospheric exposure tests and accelerated laboratory tests. Recently, an increasing interest has been paid in the use of electrochemical techniques on aluminium alloys due to their main advantages: determining of corrosion kinetics in real time and knowledge of the corrosion mechanism. This paper attempts to establish a correlation between the evolution of the impedance diagrams and the process of the attack undergone by a commercial 8090 T8171 alloy in sodium chloride solutions. During the first 100 h of immersion the electrochemical impedance spectroscopy reveals that the corrosion process is under charge transfer resistance control. After this time, the technique showed clearly the role of the adsorbed ions from the electrolyte, which promotes an intergranular attack on the alloy.