What are the materials of bicycle frame and what are its characteristics?

1. carbon steel: iron (Fe)-carbon (c) alloy without any alloying elements is carbon steel, and carbon can improve the strength in steel. The higher the carbon content, the better the strength. However, when the carbon content is higher than 0.8%, the steel is more brittle. Therefore, the frame and front fork are made of medium and low carbon steel, which has moderate strength, good plasticity and easy processing.

2. Molybdenum-chromium alloy steel:

Steel made by adding one or more total elements to carbon steel is alloy steel, in which molybdenum (Mo) and chromium (Cr) are added, which is called molybdenum-chromium alloy steel.

The role of molybdenum is to improve the strength of steel and prevent temper brittleness.

The function of chromium: corrosion resistance, rust prevention and high temperature oxidation prevention.

The strength of Mo-Cr alloy steel ranks first among alloy steels, and it is easy to reduce the weight by drawing pipes, so it has become the most commonly used material for frame and front fork. At present, the drawing name of Mo-Cr alloy steel is:

Butt joint (primary pumping) or secondary pumping, two pipe wall thicknesses.

Double docking (secondary pumping) or three-dimensional, with three wall thicknesses.

Triple docking, or four dimensions, with four wall thicknesses.

The function of tube drawing is to make the arch bridge with thin side and thick steel tube unchanged in shape strength, lighter in weight and more metallic.

3. Aluminum alloy: Aluminum is the most abundant metal on earth. Its light weight, corrosion resistance and appropriate strength allow scientists to predict that it may replace today's steel in the future. Aluminum and other metals synthesize aluminum alloys, of which copper is the most common. The use of copper in aluminum alloy is similar to that of carbon in steel, but aluminum alloy used for corrosion resistance cannot contain copper. Originally, the characteristic of aluminum is that it is easily oxidized. Fortunately, it has a higher corrosion resistance than copper and iron because oxygen flowers in the air form a very fine film of AI2 O3, which can protect the inside from oxidation. The so-called anodizing treatment can not only produce a faint AI2 O3 film on the surface of aluminum products, but also be beautiful and anti-corrosive. In addition, the surface of aluminum alloy is easy to dye, and a colored film can be grown to get the desired color.

4. Magnesium alloy: Magnesium is a highly flammable metal. Magnesium alloy is used in photography in the early days, that is, the strong light produced by the burning of magnesium powder. The weight and strength of magnesium alloy are about 2/3 of that of aluminum alloy. Although light, it is not easy to process and fragile. So at present, except for the front fork shell of ROCK-SHOX shock absorber, the general frame is rarely used.

5. Titanium alloy: Titanium (Ti) ranks fourth among the metals on the earth. The strength of titanium and its alloy is only half that of American alloy steel, and its weight and strength are only half that of American alloy steel. In addition, they have excellent corrosion resistance, which makes them necessary materials for military, aviation and aerospace industries. At present, titanium alloy tubes for bicycles are not universal. Because of its high smelting cost, welding and other processing technologies are difficult and expensive, it is difficult to be widely used.

6. Carbon fiber: Carbon fiber is a new material with high strength and light weight. Strictly speaking, it is a composite material. Other resins, glass fibers, aluminum alloys, etc. It can be mixed or overlapped according to its characteristics, and it is the lightest frame material at present. The carbon fiber tube is made of a little bit of fiber thread woven into carbon fiber cloth, made of layers of calipers, and then processed and lapped.

At present, the materials that can be used to manufacture bicycle frames are mainly as follows: steel, aluminum alloy, titanium alloy, magnesium alloy, scandium alloy, carbon fiber and so on. Generally, there are steel, aluminum alloy, titanium alloy, carbon fiber and so on. Scandium alloy and magnesium alloy are relatively rare materials that have only recently appeared.