輕量化的意義-外文文獻

附錄 AThe significance of lightweight Automotive lightweight main guiding principle: to ensure stability on basis of improved performance, energy-saving design of the assembly partscontinuous optimization model spectrum. The lightweight car, the car is to ensure strength and security of the premise, as far as possible to reduce the car's curb weight, thereby enhancing the car's power, reducing fuel consumption and reduce exhaust pollution. Experiments show that if 10% of automobile weight reduction, fuel efficiency can bincreased by 6% -8%; vehicle curb weight is reduced by 100 kg hundred kilometers can be reduced 0.3-0.6 liters; 1% of vehicle weight reduction, fuel consumption can be reduced 0.7 %. At present, due to the need for environmental protection and energy saving, lightweight car has become the world trend of automobile development. Lightweight car is the main way: ① mainstream car models continue to optimize the size, specification size to retain the main parameters of the premise, to enhance the structural strength of the vehicle, reducing the amount of supplies; ② use of lightweight materials. Such as aluminum, magnesium, ceramic, plastic, fiberglass or carbon fiber composite materials; ③ The computer design. Such as finite element analysis, local reinforcement design; ④ the use of load-bearing body, thinning the thickness of the body sheet metal. Among them, the current major automotive lightweight measures mainly the use of lightweight materials. for automotive lightweight design of the metal material The main vehicle through the car's lightweight materials to improve economy to contribute. Theoretical analysis and experimental results show thlightweight is to improve vehicle fuel economy and effective way. In order to equirements of lightweight vehicles, some new material emerged and expanded the scope of application. Nonferrous Alloys To passenger cars, the 1973 vehicle used by the non-ferrous alloy of the total timber weight ratio of 5.0% in 1980 to 5.6%, while in 1997 it reachNon-ferrous alloys in automotive applications is the rapid growth trend of development of automotive materials. Aluminum Steel aluminum density of about 1 / 3 is the most widely used lightmaterials. United States production of automotive products, for example, aluminum alloy 1976 per vehicle is only 39kg, 1982 reached 62kg, while in 1998 it reach100kg. (1) cast aluminum alloy Many elements can be used as cast aluminum alloy elements, only Si, Cu, Mg, Mn, Zn, Li in the mass production of great significance. Of course, widely used in the car is not the simple binary alloy but also a variety of elements added to obtain a good overall performance. The automobile industry is the main market of aluminum castings, such as Japan, 76% of aluminum castings, aluminum die casting 77% of automotive castings. Mainly used in aluminum alloy engine block castings, cylinder heads, pistons, intake manifold, rocker arms, engine mount bracket, air compressor connecting rod, clutch housings, clutch housings, wheels, brake parts, handles and cover shell-type parts and so on. Aluminum casting inevitably flawed, casting can not be heat treated produce a result in the use of higher strength aluminum alloy castings is limited. On the casting for this production process has been improved, semi-solid casting forging forming method and method will be used to craft the future more. (2) deformation of aluminum alloy Refers to deformation of aluminum alloy aluminum alloy plate and extrusions and forging materials, mainly used in automotive body panels on the boengine radiators, air conditioning condenser, evaporator, wheels, trim and suspension parts. As the effect is obvious lightweight, aluminum alloy car body applications is expanding. September 1990 as the Japanese started selling cars with a Honda NSX Unibody aluminum, cold rolled steel plate than in the same light 200kg body attracted worldwide attention. NSX to the entire vehicle with aluminum 31.3%, as in the aluminum car body, using the 6000 series alloy outer plate, inner plate with 5052-0 alloy, most use the 5182-0 alloy frame; that the side door of the strength and stiffness requirements are high, the use of the 6N01 alloy-based, appropriate adjustments to the Mg and Si content of the alloy. Also useful in Europe and America for 2036 and 2008 alloy plates inside and outside the body. Aluminum radiator originated in Europe and then throughout the world. In Europe, after the 1980s, aluminum radiator has occupied 90% of the market. With? Car air conditioning, oil coolers, etc. The extensive use of aluminum heat exchangers market is rapidly expanding. From the material point of view, aluminum heat exchangers in a wide range of coating material applied to a large extent due to aluminum and aluminum cladding successful development. (3) aluminum matrix composites Low density of aluminum matrix composites, strength and high modulus, good thermal fatigue properties, but in automotive applications by the price and production quality control and other constraints, have not formed a large scale. Currently, aluminum matrix composites in the connecting rod, piston, cylinder body holes, brake discs, brake calipers and other parts of the drive shaft tube test or showing superior performance, such as developed by Honda does not? Enhanced aluminum matrix composite wire rod steel rod down more than 30% weight on the 1.2L gasoline engine can increase fuel economy 5%; using chilled aluminum powder and SiC powder (weight percentage of 2%) and mixed extruded into rods, forged with the shape of the piston rod for high strength can be 20% lower weight, engine power has increased significantly; composite enhanced with aluminum piston head to cancel the first ring groove of austenitic cast iron inserts can drop weight 20%; aluminum matrix composite brake discs reduce weight than cast iron brake disc 50%. Magnesium Aluminum magnesium density of about 2 / 3, in the practical application of the metal is the lightest. Vibration absorption of magnesium alloy cutting ability is good, metal casting performance, it is suitable for manufacturing automotive parts. Most of the die casting magnesium alloy in the form of applications in the car, magnesium die casting aluminum production efficiency than the 30% to 50%. The newly developed non-porous casting method (Pore Free Diecast) can produce no holes and can be heat-treated magnesium die castings. Magnesium castings used in the car the earliest examples is the wheel rim. In the car on the trial or application instance there magnesium alloy clutch housing, clutch pedal, brake pedal mounting bracket, dashboard frame, seat, steering column parts, steering wheel round core, transmission housing, engine mounts, cylinder head and cylinder head cover and so on. With the traditional system of the steering column bracket compared to the zinc, magnesium and heavy parts down 65%; with traditional steel steering wheel core compared to 45 percent weight reduction of magnesium parts; compared with the aluminum cylinder head, magnesium parts 30% weight reduction; traditional stamping and welding structural steel brake pedal bracket compared to the overall weight of magnesium castings down 40%, while its rigidity is also improved. Magnesium matrix composites has also made progress, with SiC particles as reinforcement, mixing technology is the use of liquid magnesium-based composite materials with good performance and lower production costs. In the AZ91 alloy by adding 25% SiC particle reinforced composites than the matrix alloy with 23% higher tensile strength, yield strength increased 47%, elastic modulus increased 72%. Titanium Titanium density 4.5g/cm3, with high strength, high temperature strength and corrosion resistance and so on. Because titanium is expensive, since I saw the car in the luxury car and a small amount of individual applications. However, the application of titanium in the test car has a lot of research work. For example, with α + β titanium alloy of the engine connecting rod system, the equivalent strength quenched and tempered steel 45 levels, and weight can be reduced 30%; β of titanium (Ti-13V-11Cr-3Al, etc.) and time by the strong cold treatment, intensity of up to 2000MPa, can be used to manufacture suspension springs, valve springs and valves, etc., and the tensile strength of 2100MPa of high strength steel than titanium springs can be 20% lower weight. The biggest obstacle to the application of titanium from its high price, Toyota Central Research Institute has developed a low-cost titanium matricomposites. The composite material to Ti-6Al-4V alloy matrix to the reinforcements powder metallurgy method of production, has been applied in the engine connecting rod.