[FONT=Arial,Helvetica,Geneva,Sans-serif,sans-serif]Featherweight plastic wheel[/FONT] [FONT=Arial,Helvetica,Geneva,Sans-serif,sans-serif][SIZE=-1]Light-metal rims are popular with car fans. Fiber-composite materials offer a new option, but these wheels have not yet been approved due to a lack of suitable testing methods. Researchers can reliably simulate how they will cope with hitting the curb and negotiating bends. [/SIZE][/FONT] [SIZE=-1][FONT=Arial,Helvetica,Geneva,Sans-serif,sans-serif]Automobile wheel rims have to be able to take a lot of punishment, including curb impact, potholes and road salt. Before they can be fitted to cars, therefore, they have to undergo reliable testing to ascertain whether they are strong enough and meet the quality requirements. Standardized testing methods exist for conventional rims made of steel or aluminum. Fiber-reinforced plastics have [/FONT][/SIZE][FONT=Arial,Helvetica,Geneva,Sans-serif,sans-serif][SIZE=-1]reached the stage where they could be used for making wheels, but there is doubt as to whether the testing methods for metal wheels can be applied to them. As a result, plastic wheels have not yet been approved by Germany’s technical inspectorate, the TÜV. Manufacturer BTE Hybrid-Tech®GmbH has plenty of reason to be confident, however: the wheel rims made of fiber-plastic composite which it produced in 2001 have successfully come through tests over distances of 250,000 kilometers. The advantage of plastic wheels is that the material combines high specific strength with low weight, and it looks good as well. It consists of two main components – a matrix and reinforcing fibers. Through their interaction the two components achieve better properties in the composite material than they do separately.[/SIZE][/FONT] [SIZE=-1][FONT=Arial,Helvetica,Geneva,Sans-serif,sans-serif]The legal situation for plastic wheels could change soon, giving the designers of lightweight rims more latitude in their choice of material. Working in conjunction with colleagues from four other Fraunhofer institutes, research engineers at the Fraunhofer Institute for Structural Durability and System Reliability LBF in Darmstadt are developing a simulation method which reliably predicts the quality of the rims. “First we produce a computed tomography image of the wheel,” explains Dr. Andreas Büter, Head of Department at the LBF. “The image enables us to ascertain the length, alignment, curvature and density of the fibers. These parameters are crucial for the strength and load capacity of the material.” On the basis of these results the research scientists simulate the microstructure of the material, a virtual unitary cell in which they can for the first time depict arbitrary material configuration. Applying the results from the unitary cell, they use a numerical component model to simulate how the wheel will handle bends in the road or hitting the curb and how it would behave in a crash. “We calculate the stress and elongation occurring in the material under various loadings,” says Büter. “We know from experiments what stresses the material can withstand without being damaged and what elongations will damage it. This enables us to make a reliable assessment of plastic wheels.”[/FONT][/SIZE] [FONT=Arial,Helvetica,Geneva,Sans-serif,sans-serif][SIZE=-2]A new simulation method makes it possible to predict how a plastic wheel will respond to hitting the curb and negotiating bends. It entails calculating the position and curvature of the individual polymer fibers. (Photo: © BTE Hybrid-Tech®GmbH / Polynt GmbH)[/SIZE][/FONT] http://www.materialica.com/html/plastic_wheel.html
Curioso: no leo por parte alguna etre sus ventajas que sean más económicas (Claro que eso a los reyes del atunizaje se la traerá al pairo )
yo despues de saber la cantidad de piezas de un F1 que estan pegadas con pegamento, me lo creo todo...
Desde que en el Sema de las Vegas vi las llantas trasmarentes de metacrilato ya me creo cualquier cosa.
Todo lo que es de fibra es de plástico, la cuestión es qué carga le pongas. En el caso de la fórmula uno se usa mucho la fibra de carbono (matriz de plástico y carga o refuerzo de fibra de carbono). Los tuneros usan fibra de vidrio, mucho más barata y evidentemente con peores propiedades que el carbono. En el caso de las llantas no sé con qué las cargarán, pero si son de carbono tampoco creo que sean baratas...
hombre yo pienso que cuando las comercializan será porque han pasado unos controles de calidad y serán mas o menos fiables pero que yo no las pondria ni loco
jajaja , o los coches chinos y mira como se arrugan, por no hablar del 307 cc que ha salido por aqui hoy, eso si que es fuerte
Ya, lo digo porque el algoritmo de compresión del MP3 ha salido del Instituto Fraunhofer, como esas llantas :nah:
j*der que nivel! yo de eso no tenia ni idea lo decia porque no todo lo que se pone en el mercado es de buena calidad.
Hombre, lo digo un poco de cachondeo. Teóricamente el invento del Fraunhofer Institute para comprimir audio digital es impresionante. Pero la utilización que se hace del invento con tasas de compresión de 14:1 da como resultado un sonido de baratija que parece más propio de un "TODO A CIEN" que de un reproductor serio de audio. Pero si desarollan llantas de plástico y funcionan ya veréis como salen versiones baratas de "TODO A CIEN" :nah:
Bua... me permito decir y perdon por el vocabulario, menudas llantas de mierda xD :biglaugh: Pero bueno esque no han pensado en la refrigeracion de los frenos??? imaginate, bajando un puerto de montaña con eso... los frenos se te ponen al rojo, y las llantas, al ser de metacrilato, se funden del calor que desprenden los frenos, se te salen las ruedas y ala, ai te quedas xD madre mia.... lo que no hagan los truñeros...
Eso habría q ver como salen, xq claro está el coche por lógica tiene q arrastrar menos al pesar menos la llanta
