机械工程专业英语论文

专业英语论文考核专业年级 机械电子141 姓 名 韦 继 虎 学 号 1611140109 指导教师 董 文 彬 完成时间 2017年6月10日 1窗体顶端Application and Development of Lightweight Material for Automobile窗体底端Abstract Car lightweight is an important means to achieve energy-saving emission reduction and methods, in improving the fuel economy and environmental protection has an important role. At present, the lightweight new material is the main way of the current body weight reduction, through the multi-material structure optimization, both to improve vehicle performance, but also significantly reduce the quality. This chapter discusses the performance and application of several lightweight materials, describes the development of lightweight materials in the automotive industry and the application of the trendKey words: automotive ；lightweight ；lightweight materialsPreface窗体顶端窗体顶端 The study of lightweight car is a mainstream of modern car design and manufacturing. Car lightweight, is to ensure the strength and safety of the car under the premise of the car as much as possible to reduce the quality of the preparation, thereby enhancing the vehicles power, reduce fuel consumption and reduce exhaust pollution. Data show that if the car to reduce the quality of 10%, fuel efficiency can be increased by 6% to 8%, fuel consumption can be reduced by 6% to 10%. Fuel consumption decline, emissions also decreased, while resource utilization increased, extended life of the car, the use of performance has improved significantly. Car body quality accounts for about 50% of the quality of the vehicle, it is clear that the lightweight body for the vehicle lightweight play a pivotal role 1. At present, the car body weight reduction has two main research directions: First, the use of lightweight materials; Second, optimize the structure. Structural optimization potential space has been very small, the gradual use of lightweight new materials is the current body of one of the main means of lightweight.1 New high strength steelIn recent years, with the progress of metallurgical technology, on the basis of high-strength steel, with ultra-low carbon as the basic characteristics, and gradually formed with deep drawing, high strength, baking hardening performance of new high-strength steel. At present, the use of high-strength automotive body is mainly sheet metal and pipe. Mainly: (1) BH steel (bake hardening steel). BH steel plate yield strength in the baking paint increased, without loss of formability under the premise of improving the anti-depression, can reduce the steel plate, mainly for high strength and difficult to form parts, such as roof, Doors, luggage and other components, the main use of tensile strength of 340 390MPa BH steel plate. (2) RIP steel (phase change induced plastic steel). Mainly used for the collision must absorb more energy when the high-strength structural parts, such as body frame. (3) MS steel (martensitic phase steel). Used to hit the high impact parts, that is, in a very short collision deformation stroke to absorb a lot of energy, such as side crash protection. (4) boron steel. Used to require high strength and high degree of molding of parts, can minimize the quality. Such as A, B column reinforcement, etc. 2.Practice has proved that when the thickness of the steel were reduced 0.05,0.10,0.15 mm, the body weight loss were 6%, 12%, 18%. In terms of development trends, the use of new high-strength steel plate in the body is constantly thinning, while the body strength has increased, while increasing the safety of the car, reducing noise and vibration, improve fuel efficiency and reduce the overall quality of the car. The cost did not increase, while the acceleration, driving performance has improved. Whether from the cost point of view, or from the performance point of view, the new high-strength steel plate is to meet the lightweight body to improve the safety of the collision of the best materials. The proportion of new high-strength steel plates used in various automobile factories is increasing. Japans Mitsubishi Pajero (SPORT) for the companys latest SUV car designed a new body structure, body 70% of the components made of high-strength steel plate, the vehicles torsional stiffness even higher than the Grand Cherokee 45% Body carrying capacity of up to 2t or more. Fords Windstar body frame 60% is high strength steel. Toyotas new Vitz body structure in high-strength steel accounted for 48%, than the companys Starlet car to reduce the quality of 17kg.However, the high strength of the steel sheet is liable to cause a decrease in plasticity, a poor formability, and an increase in yield strength, which causes surface distortion and springback, and increases the shapes instability. Thus, high strength steel sheets are a difficult to form material. Thermoforming technology is a new type of high-strength stamping parts for the advanced manufacturing technology, can be used to form a strength of up to 1500MPa stamping parts, including the thermoforming process is stamping The frontier technology of the field can be widely used in the production of front and rear bumper, A-pillar, B-pillar, C-pillar, roof structure, door interior plate, door anti-collision beam and other components.2 light alloy material2.1 aluminum and aluminum alloyAluminum is the ideal choice for lightweight car, the resource is wide, lightweight, recycling, saving resources, absorbing impact energy, corrosion resistance, is the best overall performance of the basic material. The aluminum alloy used in the body is mainly deformed aluminum alloy, mainly AI-Cu-Mg system (2000 series), AI-Mg system (5000 series), AI-Mg-Si series (6000 series), AI-Mg- Zn-Cu system. Which 2000 series and 6000 series is heat treatment can strengthen the alloy, while the 5000 series is heat treatment can not strengthen the alloy. The former through the coating drying process after the strength is improved, mainly for the body outside the board and other emphasis on strength, stiffness of the site, such as car cover, hood, lift rear door, front fender, etc .; the latter excellent shape, Mainly used in the body plate and other complex parts of the shape, such as car floor structure and so on. At present, low density, high strength, high elastic modulus and superplasticity of the AI-Li alloy and aluminum anti-vibration plate, etc. has been gradually applied to the body.Aluminum alloy has good formability. Aluminum alloy body structure mainly used aluminum extrusion profiles as the main body of the space frame structure, generally with medium and strong aluminum can meet the requirements. Extrusion profiles are mainly hollow materials, in addition to light weight, high rigidity, high temperature strength, heat resistance, corrosion resistance is also very good, and can be welded, surface treatment and bending processing. The current aluminum body is made of thick-walled forged aluminum beams, and is more advantageous than stamping thin steel in terms of structural strength and stiffness, and the overall stability of the mechanism is better. Lightweight and high-strength aluminum body more solid than the traditional steel body, and do not worry about corrosion caused by the reduction of strength 3.From the aluminum panel application development trend, high strength, good forming processability, excellent surface quality aluminum plate will replace the steel plate as the main material of the car cover. The late 90s of the 20th century, there have been from the hood, fender and other parts of the body aluminum plate gradually developed into the body all the use of aluminum panels of the car, compared to steel plate by 40% to 50% of the results. Europe and the United States more developed aluminum industry, so Europe and the United States in the aluminum car to go ahead Europe and the United States and Japan in the automotive industry competition and its domestic energy and environmental legislation to promote the acceleration of the car lightweight (aluminum) pace. Germany Audi A8 sedan body are made of aluminum, the framework of three-dimensional frame structure, the cover for the aluminum stamping, was rated as one of the worlds important scientific and technological achievements in 1994 one of the 100. This aluminum body compared with the steel body, the quality of 30% to 50%, fuel consumption reduced by 5% to 8%. Japan Hondas car body with aluminum alloy up to 162kg, steel body weight loss of about 40%. And Chinas aluminum production, prices, the comprehensive impact of the technical level of the automotive industry, making aluminum and its alloys still can not be used in a large number of cars. Increase the variety, improve quality and reduce costs, has become Chinas aluminum processing industry and the automotive industry to the worlds advanced level of development research。Specific strength and specific stiffness of aluminum metal-based composite materials research and development success for the further development of automotive lightweight provides a way. Germanys Kaman company developed a laminated aluminum, the outer layer is aluminum, the middle is foam aluminum, used as body panels, stiffness increased by 10 times, while the quality of 50%. Hyundai is developing a high-performance, high-speed, safe, comfortable, energy-saving and low-pollution direction. The development of high-performance automotive aluminum alloy and the recycling of scrap automotive materials has become an imperative issue. Scientific research and investment will bring huge economic and social benefits. With the rapid solidification of aluminum alloy, powder metallurgy aluminum alloy, superplasticity aluminum alloy, aluminum composite materials and foam aluminum and other new materials development and application of the future aluminum in the automotive application will be further expanded, and will show castings, Profiles, plates simultaneously situation. Aluminum is expected to be the second largest automotive material after steel 4.2.2 magnesium alloyMagnesium alloy is a lighter weight material than aluminum alloy, heat, pressure, corrosion resistance and easy to use, is a typical green structural materials. At present, the deformation of the magnesium alloy material for the body structure of the United States developed high strength ZK60 deformation of magnesium alloy, developed by Japan ultra-high strength IM Mg - Y deformation of magnesium alloy, and can be cold processing of magnesium alloy sheet. Europe is using and developing more than 60 kinds of magnesium alloy auto parts. Germany to fly more cooperation with the German Volkswagen, ready to replace its patented product magnesium alloy Mn E21 a car car body parts, such as front and rear bumper, roof beams and door anti-collision rods and so on. If the success of the replacement, will greatly reduce the cars body quality 5.China is a large resource of magnesium, magnesium ore products and more species, rich reserves, accounting for the worlds available magnesium reserves of about 70% of reserves. 2010 magnesium alloy production line in Chinas Shanxi, Shaanxi, Tianjin, Ningxia, Chongqing and other places put into operation, including magnesium-based alloy auto parts project has been in the development and production. Magnesium alloy in the automotive application increased year by year, is expected in the next 20 years, the amount of magnesium on the car will be more than 100kg per vehicle, is the current use of 30 times. Magnesium will become a new material for most structural parts of the car.3 engineering plastics and composite materialsEngineering plastics and composites are another important type of automotive lightweight material. Compared with the general plastic, engineering plastics have excellent mechanical properties, chemical resistance, heat resistance, wear resistance, dimensional stability and other characteristics, than the replacement of metal materials and light energy when molding less. At present, most of the engineering plastics used in the body inside and outside the trim, such as body fender, rear panel, dashboard, door panels, ceiling, side liner lining, door anti-collision, handrails, windows, heat Cover, and so on. Compared to metal can be reduced by 40%, and can withstand erosion and slight collision, in the case of low-speed collision without maintenance, from the manufacturing point of view compared to metal has greater freedom of modeling to enhance, but also facilitate the integration of parts, from the pedestrian protection Consider, is also ideal material. Ford developed the LTD test car, plastic body after the lightweight aspects of the obvious results, the vehicle weight loss of up to 300kg or more. The scope of application of engineering plastics in automobiles is expanding from interior parts to exterior parts, bodywork and structural parts. The future development direction is to develop structural parts, reinforced plastic composites for exterior parts, high performance resin materials and plastics, and Will pay more attention to the recyclability of materials.Fiber reinforced plastic is a composite fiber and plastic composite materials. Commonly used is glass fiber and thermosetting resin composite material. This kind of composite material has the advantages of small density, flexible design, easy molding, corrosion resistance, heat insulation, impact resistance, anti-vibration, easy coating, high strength, high elastic modulus, mechanical properties similar to metal materials, Under certain conditions, there is a metal sheet can not match the advantages of quality reduction and strength to achieve even more than the aluminum, while the overall cost is lower. At present in the car body has been widely used in the useful glass fiber reinforced unsaturated polyester chip molding compound (SMC) manufacturing body air deflector, the front fender and the front fender extension parts, headlamps, hood, Decorative pieces, tail plate, etc .; with the transfer molding technology (RTM) manufacturing body plate stiffeners, etc.Carbon fiber (CFRP) is a fibrous filamentous composite material, which needs to be woven into a sheet like a woven fabric during the molding process and is wetted and cured with an organic glue. Carbon fiber reinforced polymer matrix composites have excellent toughness and tensile strength, and the quality of steel only 1/4 6. Lightweight, high-strength features are required for high-performance cars, the current Ferrari, Lamborghini and other sports car body made of carbon fiber. CFRP is expected to use the car body to reduce the quality of 40% to 60%, equivalent to the quality of steel 1/3 to 1/6. However, due to the high cost of carbon fiber reinforced composites, its use in the automotive industry is limited. In order to reduce the cost of carbon fiber reinforced composites and increase the amount of carbon fiber reinforced composites, the production methods and processes of carbon fiber reinforced composites have become important research topics in the research of lightweight materials.The textile composite material is composed of the textile structure and the matrix material. The combination of the textile technology and the modern composite material forming technology effectively overcomes the shortcomings such as the orientation of the traditional composite material and the nonuniformity of the mechanical properties and the low damage tolerance, Specific strength and specific modulus, anti-fatigue performance, in the automotive industry more and more widely. Flexible textile composite materials are mainly used in the body inside and outside the decoration and automotive pipe, strip; rigid textile composite materials can be made body parts.4 concluding remarksThe current body material is still high strength steel, aluminum, magnesium and plastic-based. With the new materials, new technology, new technology research and development, lightweight materials and automotive product design, manufacturing process will be more closely integrated, automotive body materials will tend to multi-material lightweight design direction. Through the optimization of multi-material structure, both to improve vehicle performance, but also significantly reduce the quality. To achieve multi-material lightweight structure design, we must emphasize that the right materials used in the right parts.Bibliography1 Ao Bingqiu. The latest developments in lightweight automotive materials technology J. Automotive Technology and Materials, 2002,9 (8): 5-7.2 Feng Meibin. Development and application of new materials in vehicle lightweight technology J. Automotive Engineering. 2006, 28 (3): 24-26.3 Guan Shaokang. Research status and development trend of automobile aluminum alloy body plate J. Mechanical Engineering Materials, 2001, 25 (5): 13-14.4 Niu Shengfu. Automobile body lightweight technology J. Shanghai Automotive, 2009,12 (9): 34 - 35.5 Shi Xiuzhong. Application of lightweight materials in the field of automotive applications J. Journal of Liaoning Institute of Science and Technology, 2009,11 (4): 11-12.6 Zhu long hair. Application of High Strength Steel Plate in Automobile Body and Its Countermeasure J. Wuhan Iron and Steel Technology, 2007,45 (2): 43-45 IX 汽车轻量化材料的应用及发展现状摘要：汽车轻量化是实现节能减排的重要手段和方法，在提高汽车燃油经济性和环保方面有重要作用。目前，轻质新材料是当前车身轻量化的主要途径，通过对多材料结构进行优化，既能改进汽车性能，又能显著减小质量。本章论述了几种轻量化材料的性能及运用，阐述了轻量化材料在汽车领域的发展现状及应用趋势。关键词：汽车 轻量化 轻质材料0 前言汽车轻量化研究是现代汽车设计制造的一大主流。汽车轻量化，是在保证汽车强度和安全性的前提下，尽可能降低汽车的整备质量，从而提高汽车的动力性，减少燃料消耗，降低排气污染。资料表明，若汽车质量减轻10%，燃油效率可提高6%8%，油耗可降低6%10% 。燃油消耗下降，排放也随之减少，同时资源利用率提高，汽车使用寿命延长，使用性能也有显著提高。轿车车身质量约占整车质量的50%，显然，车身轻量化对于整车轻量化起着举足轻重的作用1。目前，汽车车身轻量化主要有 2 个研究方向: 一是采用轻质材料; 二是优化结构。结构优化潜力空间已很小，逐步采用轻质新材料是当前车身轻量化的主要途径。1 新型高强度钢近年来，随着冶金技术的进步，在高强度钢的基础上，以超低碳为基本特征，逐步形成了具有深拉伸性、高强度、烘烤硬化等性能的汽车新型高强度钢。目前汽车车身使用的高强度钢主要是板材和管材。主要有:(1)BH 钢( 烘烤硬化钢)。BH 钢板的屈服强度在烘烤涂漆时升高，可在不损失成形性的前提下，提高抗凹陷性，可减薄钢板，主要用于要求高强度且成型困难的零件，如车顶、车门、行李箱等部件，主要使用抗拉强度为 340390MPa 的BH 钢板。(2) RIP 钢 (相变诱发塑性钢)。主要用于发生碰撞时必须吸收较多能量的高强度结构件，如车身框架等。(3)MS 钢( 马氏体相位钢) 。用于对防撞要求很高的零件，即在很短的碰撞变形行程内要吸收大量的能量，如侧面防撞保护件。(4)硼钢。用于要求高强度和高成型度的零件，可以最大限度地减轻质量。如 A、B 柱加强件等2。实践证明，当钢板厚度分别减少 0.05，010，015mm 时，车身减重分别为 6% ，12% ，18% 。就发展趋势而言，车身采用新型高强度钢板在不断减薄，而车身强度却提高了，同时增加了汽车的安全性，降低了噪声和振动，提高了燃油效率，降低了汽车总质量。成本没增加，而加速性、驾驶性能却有所改善。不论从成本角度，还是从性能角度分析，新型高强度钢板是满足车身轻量化、提高碰撞安全性的最佳材料。各汽车制造厂的新型高强度钢板使用比例正在不断提高。日本三菱公司的帕杰罗( SPORT) 为该公司最新的 SUV 型车设计了全新的车身结构，车身 70% 的构件由高强度钢板制成，整车的扭转刚度甚至比大切诺基还要高 45% ，车身的承载能力可达 2t 以上。福特的 Windstar 车身骨架60% 是高强度钢。丰田最新的 Vitz 车身结构中高强度钢占48% ，比该公司生产的 Starlet 车减轻质量 17kg。但钢板高强度化易引起塑性下降，成形性变差，而屈服强度的提高则引起面畸变和回弹效应，增加了形状的不稳定性。因而，高强度钢板是一种难以成形的材料。典型的成形缺陷有开裂、形状不良、尺寸精度不良和卡模具等。热成形技术是一项新型的专门用于成形高强度冲压件的先进制造技术，可用来成形强度高达 1500MPa 的冲压件，目前成为世界上众多汽车厂商关注的焦点，其中温热成形工艺是冲压成形领域的前沿技术，可广泛应用于汽车前后保险杠、A柱、B柱、C柱、车顶构架、车门内板、车门防撞梁等构件的生产。2 轻合金材料2 1铝及铝合金铝材是汽车轻量化最理想的选择，资源广、轻量化、再生利用、节约资源、吸收冲击能、耐腐蚀，是综合性能最佳的基本材料。用于车身上的铝合金主要是变形铝合金，主要有 AICuMg系(2000系) 、AIMg系(5000系) 、AIMgSi 系(6000系)、AIMgZnCu 系。其中 2000 系列和 6000系列是热处理可强化合金，而 5000 系列是热处理不能强化合金。前者通过涂装烘干工序后强度得到提高，主要用于车身外板等重视强度、刚度的部位，如车厢盖、发动机罩、提升式后车门、前端翼子板等; 后者成形性优良，主要用于车身内板等形状复杂的部位，如车厢底板结构件等。目前，低密度、高强度、高弹性模量和超塑性优良的 AILi合金及铝防振板等现已逐步应用于车身上。铝合金具有良好的成型性。铝合金车体结构主要采用以铝挤压型材为主体的空间框架结构，一般用中强铝材便可满足要求。挤压型材主要是采用空心材，除质量轻、刚性高以外，高温强度、耐热性、耐蚀性等也很好，而且可以进行焊接、表面处理和弯曲加工。目前的铝制车身多采用厚壁锻铝梁焊接而成，就结构强度和刚度而言要比冲压薄钢更有优势，且机构的整体稳定性更好。轻量化且高强度的铝制车身比传统钢制车身更坚固，且不用担心腐蚀造成的强度降低3。从铝板覆盖件的应用发展趋势看，强度高、成形加工性好、表面质量优良的铝板将取代钢板成为汽车覆盖件的主要材料。20世纪90年代末期，就已出现了从发动机罩、翼子板等部分车身铝外板逐步发展为车身全部采用铝外板的轿车，相对钢板获得了减40%50%的效果。欧美铝工业较发达，所以欧美在汽车铝化方面走在前头。欧美等国与日本在汽车业上的竞争和其国内能源及环境立法的推动，加速了汽车轻量化( 铝材化) 的步伐。德国奥迪 A8 型轿车车身均采用铝材制造，框架采用立体框架式结构，覆盖件为铝板冲压而成，曾被评为 1994