Automobiles composites applications

Recently, metal matrix composites containing a high volume fraction of reinforcement (>50 vol.%) have been developed for automobile brake applications [2,4] and for electronic appliances, such as microwave housings and heat sinks [6]. 

One of the key factors which make plastics attractive for engineering applications is the possibility of property enhancement through fibre reinforcement. Composites produced in this way have enabled plastics to become acceptable in, for example, the demanding aerospace and automobile industries. Currently in the USA these industries utilise over 1(X),000 tonnes of reinforced plastics out of a total consumption of over one million tonnes. 

We just cannot expect situations like golf clubs and tennis rackets for all consumer products because all products do not have those same built-in characteristics of the competitive edge. When we consider a car, we must be realistic and acknowledge that the car must have a price low enough for people to afford. Think back to the days of Henry Ford he made a car that could be sold for about 250, so that everyone could afford to have one. This affordability was the real beauty of his mass-production techniques. Everyone could afford to have a car, and then almost everyone did have one. In contrast, before Henry Ford, only the rich could afford an automobile. As soon as we get to the trade-off where composite materials will effectively compete in the automotive market place, we will see tremendously broader applications, but there are problems along the way. The manufacturing cost must be improved in order for those applications to ever come about. 

Composite deposits of electroless nickel and PTFE are characterised by a very low coefficient of friction . They contain 18-25% by volume of PTFE, and have found considerable application in the automobile, textile machinery and paper-making industries, among others. 

Cereal, corn, barley. .. into matrices of PP, PE, ABS, PVC. Composite moduli are claimed in the range of 1.5-3 GPa for prices in the order of 0.75 to 3 per kg. Applications could be in packaging, toys, building and automobile. The properties of the Epitex PP composites are, for example ... 

Butadiene can form three repeat units as described in structure 5.47 1,2 cw-1,4 and trans-, A. Commercial polybutadiene is mainly composed of, A-cis isomer and known as butadiene rubber (BR). In general, butadiene is polymerized using stereoregulating catalysts. The composition of the resulting polybutadiene is quite dependent on the nature of the catalyst such that almost total trans-, A, cis-, A, or 1,2 units can be formed as well as almost any combination of these units. The most important single application of polybutadiene polymers is its use in automotive tires where over 10 t are used yearly in the U.S. manufacture of automobile tires. BR is usually blended with NR or SBR to improve tire tread performance, particularly wear resistance. 

Composites are being employed in a number of automotive applications. These include racing car bodies as well as regular automobiles. Most automobiles have the lower exterior panels composed of rubbery, plastic blends, and/or composite materials. Corvettes have composite bodies that allow a lightweight vehicle with decent fuel economy and they do not rust. Other parts such as drive shafts and leaf springs in private cars and heavy trucks, antennas, and bumpers are being made from composite materials. 

Riedel, U., Nickel, J. (2003). Applications of natural fiber composites for constructive parts in aerospace, automobiles, and other areas. In A. Steinbiichel (Ed.). Biopolymers, vol. 10 (pp. 1-11). Wiley-VCH, New York. 

In fact, most of us benefit from the use of catalysis. Automotive catalytic converters have represented the most massive application of environmental catalysis and one of the most challenging and successful cases in catalysis, generally. Automobile catalysts deseive a few more comments. The engine exhaust emission is a complex mixture, whose composition and flow rate change continuously depending on a variety of factors such as driving conditions, acceleration, and speed. Despite the variability of the conditions, three-way catalysts have achieved the reduction of exhaust carbon monoxide, hydrocarbons, and... 

However, there are several major drawbacks that hinder practical application of this NOx reduction method in automobile exhaust aftertreatment (i) The NO reduction activity is typically limited to a certain temperature window, for NM-based catalysts it is around the light-off—cf. Fig. 14 and Ansell et al. (1996), Jirat et al. (1999b), Burch et al. (2002) and Joubert et al. (2006). (ii) With low HC concentrations and the exhaust composition met in modern diesel engines, the achieved NOx conversions in real driving cycles are quite low (typically around 5-10%, cf., e.g., Kryl et al, 2005). (iii) The selectivity of NOx reduction is problematic, N20 may form up to 50% of the product (Burch et al., 2002 Joubert et al., 2006). Alternative (Cu-, Co-, Ag-, etc., based) catalysts may provide a wider temperature window or better selectivity for... 

The most important and established use for pigments is the imparting of color to a variety of materials and compositions. Examples are surface coalings for exteriors and interiors of automobiles and houses wilh odor water-based paints W ood stains, leather and artificial leather finishes, printing inks and many other applications. 

Another important application of heterogeneous catalysts is in automobile catalytic converters. Despite much work on engine design and fuel composition, automotive exhaust emissions contain air pollutants such as unburned hydrocarbons (CxHy), carbon monoxide, and nitric oxide. Carbon monoxide results from incomplete combustion of hydrocarbon fuels, and nitric oxide is produced when atmospheric nitrogen and oxygen combine at the high temperatures present in an... 

Several length-scales have to be considered in a number of applications. For example, in a typical monolith reactor used as automobile exhaust catalytic converter the reactor length and diameter are on the order of decimeters, the monolith channel dimension is on the order of 1 mm, the thickness of the catalytic washcoat layer is on the order of tens of micrometers, the dimension of the pores in the washcoat is on the order of 1 pm, the diameter of active noble metal catalyst particles can be on the order of nanometers, and the reacting molecules are on the order of angstroms cf. Fig. 1. The modeling of such reactors is a typical multiscale problem (Hoebink and Marin, 1998). Electron microscopy accompanied by other techniques can provide information on particle size, shape, and chemical composition. Local composition and particle size of dispersed nanoparticles in the porous structure of the catalyst affect catalytic activity and selectivity (Bell, 2003). 

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