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Bicycle

By Ragad and Hiba

+The History of Bicycle: In 1816 the German Baron Karl von Drais devised a steerable

hobby horse, and within a few years, hobby-horse riding was a fashionable pastime in Europe. Riders also discovered that they could ride the device with their feet off the ground without losing their balance. And so, in 1840, a Scottish black-smith named Kirkpatrick Macmillan made a two-wheel device that was operated by a treadle. A couple decades later, a Frenchman, Ernest Michaux, designed a hobby horse that utilized cranks and rotating pedals connected to the front axle.

+What Materials used in Bicycle??The old bicycle made of: Steel.

aluminum

The new bicycle made of: Steel

Aluminum

Titanium

Carbon fiber

+Steel: The chemical formula of the steel

is Fe3C.

The properties of steel vary widely, depending on its alloying elements.

The production of steel benefits the World in great ways. First, the standard of living goes higher as there exist new jobs in banking, iron ore and manganese mining, office jobs, transport jobs.

The steel recycle. If we only recycle one-tenth of the cans we now throw away, we'd save about 3.2 billion of them every year.

+Advantage and Disadvantages:

Advantage: Steel has the highest strength

to weight ratio of any building material.

No twisting or warping. Fire parapets can be

eliminated. Slower aging process with

less maintenance. Easily disassembled for

repairs

Disadvantages: Heavy and thus expensive to

transport. Steel is an excellent thermal

conductor requiring additional exterior insulation or thermal breaks to overcome this disadvantage

Steel components can rust if left exposed in marine climates.

Finding steel roof trusses is difficult in most areas

+Aluminum: The chemical formula of aluminum

is A13.

Aluminum is a metallic element, and its structure is very similar to most other metal.

Aluminum is made up of crystals

It is not soluble in water under.

Aluminum is the most abundant metal in the Earth's crust.

Recycling aluminum cans is easy. When they are empty, rinse them out so they are clean and either return them to the store for deposit or recycle

+Advantage and Disadvantages:

Advantage: Won't swell, chip or rust. Does not deteriorate. Reduced weight. increased strength &

durability. Covers can be retrofitted

for existing structures. Low Surface Hardness

Disadvantage: Aluminum is more

expensive than steel Aluminum can corrode

quickly if suitable precautions against electrolysis are not taken.

Aluminum can be water-stained easily.

+Titanium:

Titanium is chemical element with the symbol Ti and atomic number 22.

Transition metal with a silver color.

White metal when pure. Titanium is as strong as

some steels. Titanium is transition metal. The metal has a low density.

+Advantage and Disadvantages:

Advantage: It is corrosive resistant. It can withstand high

temperatures. Light but Strong. has excellent corrosion

resistance.

Disadvantages: Expensive metal. Processes for forming and

joining titanium are complex and expensive.

Expensive to cast.

+Carbon fiber

There is no single formula for a carbon fiber. is a

Carbon fiber is crystalline material.

White metal when pure. High chemical resistivity. Rigid materials that are

resistant to stretching and compression.

a black, lustrous solid

+Advantage :

Advantage: It can be formed to most any shape. it's non-corroding. High wear resistivity and moisture absorbance. High thermal resistivity under non oxygen atmosphere. High modules {200~650Gpa} and high rigidity.

+Old and new bicycle:1. It should be fast, have all the size for all the ages, easy to

transfforing, and something doesn’t rust light.2. The bicycle change because they want the rider more comfortable.3. The heavy materials make the movement hard, but now the light materials make the movement more easier then the old bicycle.

+ http://www.cksinfo.com/clipart/traffic/bicycles/bicycle-yellow.png http://3.bp.blogspot.com/_473nrD5vEv8/SLfbra-cE-I/AAAAAAAAAvA/TqwXU4i-37o/s4

00/old-bicycle.jpg http://ezinearticles.com/?Comparison-of-Bicycle-Frame-Materials&id=692567 http://www.exploratorium.edu/cycling/frames1.html\ http://www.marketresearchlatinamerica.com/wp-content/colombia_steel.jpg http://www.oberlin.edu/recycle/facts.html http://wiki.answers.com/Q/What_are_the_advantages_and_disadvantages_of_steel_as

_a_structural_material http://www.mainrecycling.com/_images/products/AluminumWheels.jpg sam.davyson.com/.../aluminium/.../structure.html http://en.wikipedia.org/wiki/Aluminium http://www.temcor.com/alum_advantages.php http://www.gharexpert.com/articles/Aluminium-Doors-192/What-advantages-disadva

ntages-Alumi_0.aspx http://www.sydneyoraldesign.com.au/new_titanium.htm http://www.webelements.com/titanium/contents.html

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We hope you like it.By Hiba and Ragad