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金属腐蚀的电化学方面的中英文对照的论文 两者分开,奖励50财富值

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金属腐蚀的电化学方面的中英文对照的论文 两者分开,奖励50财富值【专家解说】:金属材料的腐蚀与防腐措施研究摘要:金属材料具有高强度、优良的塑性和韧性,耐热、耐寒,可铸造、锻造、冲

【专家解说】:金属材料的腐蚀与防腐措施研究 摘要:金属材料具有高强度、优良的塑性和韧性,耐热、耐寒,可铸造、锻造、冲压和焊接,还有良好的导电性、导热性和铁磁性,因此,金属材料的腐蚀与防腐研究有很重要的意义。 关键词:金属材料 腐蚀 防腐 金属材料是一种历史悠久发展成熟的工程材料。我国早在商朝即有青铜器出现,春秋战国时代开始使用铁器,铝合金的运用亦已有一百年的历史,就连钛合金都已发展六十多年了,随着人类文明的演进,金属材料一直扮演着重要的角色,举凡与我们生活息息相关的食,衣,住,行,无不处处见其踪迹。 1、金属材料的发展历程 面对21世纪人类科技虽然已推进到太空时代,电子资讯时代,各种新兴的材料如高分子材料,半导体材料,光电材料的白热化竞争,金属材料却未因而失去其魅力,反之在电脑,程控,材料等科技的支援下,金属材料不断开发出新的应用领域,仍是充满着无限发展的生命力。如钢铁材料的年用量从战后的不足二亿吨,以快速的成长到目前的七亿多吨,是仅次于混凝土用量排名第二的工程材料,而铝、镁、钛因其轻金属的一些特性,成为电子资讯产业中新兴的结构材料,用于机壳内构件,以及支架。 虽然轻金属应用与制造由来已久,但是在新兴产业中直未受到太大的关注,直到20世纪80年代中期开始,欧美汽车工业希望朝轻量化发展时,才开始重视轻金属的应用。轻金属合金因为符合能源节约,降低空气污染,可回收再生及制程清洁环保等诉求,所以逐渐受到重视且已应用在实际产品上,现今商品汰换速度极快,产品使用周期缩短而大量增加废弃产品。 世界各国均订定相关环保法令,要求厂商回收报废产品。轻金属大多具有易回收再利用之优点,此外精炼技术的不断改善,也大幅增加了回收效率,更充分达到资源再利用的目的。铝合金发展至今已超过100年以上,因此应用范围极广,成为重要的基本材料之一,其规模仅次于钢铁工业,远大于镁合金,钛合金及工程塑胶等结构材料产业。如今,除了航空工业之外,日常生活用品也有许多应用铝合金的产品,例如铝门窗,自行车架甚至铝箔包都是。笔记型电脑厂商也已经推出了铝合金外壳之笔记型电脑,而运输工具轻量化更是各国业者汲汲努力的目标。 2、金属材料的腐蚀 金属材料的腐蚀,是指金属材料和周围介质接触时发生化学或电化学作用而引起的一种破坏现象。由于金属材料的腐蚀可造成设备的跑、冒、滴、漏,污染环境,甚至发生中毒、火灾、爆炸等恶性事故以及资源和能源的严重浪费。因此,研究金属材料的腐蚀机理,弄清腐蚀发生的原因及采取有效的防护措施,对于延长设备寿命、降低成本、提高劳动生产力都具有十分重大的意义。 2.1金属腐蚀的分类 按照金属的腐蚀机理可以将金属腐蚀分为化学腐蚀与电化学腐蚀两大类。不管是化学腐蚀还是电化学腐蚀,金属腐蚀的实质都是金属原子被氧化转化成金属阳离子的过程。 2.2金属腐蚀的机理 2.2.1化学腐蚀 化学腐蚀是指金属与非电解质直接发生化学作用而引起的破坏其腐蚀过程是一种纯氧化和还原的纯化学反应,即腐蚀介质直接同金属表面的原子相互作用而形成腐蚀产物。反应进行过程中没有电流产生,其过程符合化学动力学规律。 2.2.2电化学腐蚀 电化学腐蚀是金属与电解质溶液发生化学作用而引起的破坏。反应过程同时有阳极失去电子,阴极获得电子以及电子的流动,其历程服从电化学的基本规律。电化学腐蚀又根据其电解质溶液酸碱性的不同分为吸氢腐蚀和析氢腐蚀。 3、金属材料的主要防腐措施 3.1改善金属的本质 根据不同的用途选择不同的材料组成耐蚀合金,或在金属中添加合金元素,提高其耐蚀性,可以防止或减缓金属的腐蚀。如,在钢中加入镍制成不锈钢可以增强防腐蚀的能力。 3.2形成保护层 在金属表面覆盖各种保护层,把被保护金属气腐蚀性质隔开,是防止金属腐蚀的有效方法。工业窿辅使用的保护层有非金属保护层和金属保护层两大类,通常采用以下方法形成保护层: 1)金属的磷化处理:钢铁制品去油、除锈后,放入特定组成的磷酸盐溶液中浸泡,即可在金属表面形成一层不溶于水的磷酸盐薄膜,这种过程叫做磷化处理。磷化膜呈暗灰色至黑灰色,厚度一般为5至20微米,在大气中有较好的耐蚀性。膜是微孔结构,对油漆等的吸附能力强,如用作油漆底层,耐腐蚀性可进一步提高。 2)金属的氧化处理:将钢铁制品加到Na0H和NaN02,的混合溶液中,加热处理,其表面即可形成一层厚度约为0.51.5微米的蓝色氧化膜(主要成分Fe3O4),以达到钢铁防腐蚀的目的,此过程称为发蓝处理,简称发蓝。这种氧化膜具有较大的弹性和润滑性,不影响零件的精度。故精密仪器和光学仪器的部件,弹簧钢、薄钢片、细钢丝等常用发蓝处理。 3)非金属涂层:用塑料喷涂金属表面,比喷漆效果更佳。塑料覆盖层致密光洁。色泽艳丽,兼具防蚀与装饰的双重功能。搪瓷是含SiO:量较高的玻璃瓷釉,有极好的耐腐蚀性能,因此作为耐腐蚀非金属涂层,广泛用于石油化工、医药、仪器等工业部门和日常生活用品中。 4)金属保护层:这是以一种金属镀在被保护的另一种金属制品表面上所形成的保护镀层,前一种金属称为镀层金属。金属镀层的形成,除电镀、化学镀外,还有热浸镀、热喷镀、渗镀、真空镀等方法。 metal Corrosion and Corrosion Measures Abstract: The metal material has high strength, excellent ductility and toughness, heat, cold, may be casting, forging, stamping and welding, but also good electrical conductivity, thermal conductivity and ferromagnetism, therefore, metal corrosion and corrosion of materials There are important. Key words: corrosion of metal corrosion metal material is a long history of engineering materials developed. In the early Shang Dynasty bronzes that have occurred, the Warring States era began using iron, the use of aluminum and there has been a hundred years of history, even the development of titanium alloys have been 60 years, with the evolution of human civilization, the metal material has been play an important role in that whenever our lives, food, clothing, housing, transportation, are all reflected in its traces everywhere. 1 Development of metallic materials Although the face of 21st century human technology has advanced to the space age, electronic information age, a variety of new materials such as polymer materials, semiconductor materials, optoelectronic materials, competing in the metal material has not lose its charm, whereas in the computer, program-controlled and material support of science and technology, metal and constantly develop new applications, is still filled with endless vitality. Materials such as steel consumption from the post-war years, less than 200 million tons, with fast growth to the current more than 700 million tons, second only to the second largest amount of concrete construction materials, and aluminum, magnesium, titanium because of its light metal Some features, a new electronic information industry in the structure of materials, for chassis components, and support. Although the manufacture of light metal applications and long, but not directly in the emerging industry are significant concerns, until the mid-80s of the 20th century, Europe and the United States hope that the DPRK lightweight automotive industry development, only being the application of light metal. Light metal alloy for consistent energy savings, reduce air pollution, renewable and recyclable system for Cheng Qingjie environmental protection demands, it has become an important and has been used in actual products, today's fast product replacement, product cycles and a significant increase in waste products . Countries in the world are set to relevant environmental laws, requiring manufacturers to recall products scrapped. Most of light metal with the advantages of easily recyclable, in addition to refining technology continues to improve, greatly increased the recovery efficiency and use resources more fully achieve the purpose. Aluminum alloy development has been more than 100 years, so a very wide range of applications, an important basic material for a scale second only to iron and steel industry, much larger than magnesium alloy, titanium and other structural materials and engineering plastics industry. Now, in addition to the aviation industry, the daily necessities, there are many applications aluminum products, such as aluminum doors and windows, bicycle rack or aluminum foil package is. Notebook manufacturers have introduced aluminum shell of the notebook, but it is lightweight transport industry as striving States goal. 2, the corrosion of metal materials Corrosion of metallic materials, is the metal contact material and the surrounding medium a chemical or electrochemical action resulting from a destructive phenomenon. As the corrosion of metallic materials can cause equipment to run, run, drip, leak, polluting the environment, and even poisoning, fires, explosions and bad accidents and serious waste of resources and energy. Therefore, the corrosion mechanism of metal materials and understand the causes of corrosion occurs and take effective protective measures, for longer equipment life, reduce costs and improve labor productivity are of great significance. 2.1 Classification of metal corrosion In accordance with the mechanism of metal corrosion can be divided into chemical corrosion of metal corrosion and electrochemical corrosion two categories. Either chemical etching or electrochemical corrosion, metal corrosion is the essence of metal atoms into the oxidation process of metallic cations. 2.2 The mechanism of metal corrosion 2.2.1 Chemical etching metals and chemical corrosion is a chemical effect of non-electrolyte direct damage caused by the corrosion process is a pure oxidation and reduction of the pure chemical reaction, that is corrosive metal surface atoms directly interact with the formation of corrosion products. Reaction process is not currents, consistent with the chemical kinetics of the process. 2.2.2 Electrochemical Corrosion Electrochemical corrosion of metal and the electrolyte solution caused by a chemical role in the destruction. Anode reaction at the same time there is loss of electronic access to electronic and electronic cathode flow, the process to obey the basic laws of electrochemistry. Electrochemical corrosion and, in its different acidity of electrolyte solution into hydrogen corrosion and hydrogen corrosion. 3, the main corrosion of metal materials measure 3.1 improve the nature of metal Depending on the composition of different materials used corrosion resistant alloys, or metal alloy elements added to improve corrosion resistance, can prevent or slow down the corrosion of metals. For example, in steel containing nickel made of stainless steel can enhance the anti-corrosion. 3.2 form a protective layer metal surface covered in a variety of protective layer, the corrosion of the protected nature of metal separated by air is an effective way to prevent metal corrosion. Industrial hole secondary layer of protection to use a non-metallic coating and the metal protective layer two categories, usually form a protective layer of the following methods: 1) metal phosphate treatment: iron and steel products to oil, rust, into a specific form of the phosphate solution, soaking the metal surface can form a thin film of water-insoluble phosphate, this process is called phosphating treatment. Phosphate film was dark gray to dark gray, the thickness of 5 to 20 microns, in the atmosphere has good corrosion resistance. Membrane is the microporous structure of the painting's absorption capacity, such as bottom paint, corrosion resistance can be further improved. 2) oxidation of metals: iron and steel products will be added to Na0H and NaN02, the mixed solution, heat treatment, the surface can form a layer thickness of about 0.51.5 micron blue oxide film (the main component Fe3O4), in order to to achieve the purpose of corrosion of steel, this process is known as blueing treatment, short hair blue. This oxide film has greater flexibility and lubrication, does not affect the part accuracy. Therefore, precision instruments and optical equipment parts, spring steel, thin steel sheet, steel wire and other common hair blue handle. 3) non-metallic coatings: metal surface with a plastic coating than paint a better effect. Dense layer of smooth plastic cover. Beautiful color, both the dual function of corrosion and decoration. Enamel is with SiO: glass with high enamel, with excellent corrosion resistance, and as a corrosion-resistant metallic coatings, widely used in petrochemical, pharmaceutical, equipment and other industrial sectors and the daily necessities of. 4) The metal protection layer: This is a metal-plated another in the protected metal surface protective coating is formed, called the former metal plating metal. The formation of metal coatings, in addition to electroplating, electroless plating, there are hot dip, hot spraying, diffusion coating, vacuum plating and other methods.
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