Five key knowledge points that the aluminum industry must know!
1, Why is aluminum called the 'flying metal'?
The density of aluminum is very small, only 2.7g/cm ³. It has a dense layer of Al ₂ O ∝ film on its surface, which protects the aluminum inside from oxidation. 70% of modern aircraft are made of aluminum and aluminum alloys, hence aluminum is known as the 'flying metal'.
2, Why is aluminum usually trivalent?
The outer electron configuration of aluminum atoms is 2, 8, 3. Due to the insufficient number of outermost electrons and unstable structure, aluminum is prone to losing three electrons, resulting in frequent positive trivalent reactions. Although aluminum is more reactive than sodium and magnesium, its three electrons are more stable than one electron in sodium and two electrons in magnesium.
3, Why do aluminum profiles need surface treatment?
If aluminum profiles are not surface treated, their appearance will not be aesthetically pleasing and they are prone to corrosion in humid air. In order to improve the decorative effect, enhance corrosion resistance, and extend the service life, aluminum profiles generally need to undergo surface treatment.
4, Why is aluminum more expensive than iron?
Although aluminum has more reserves in the Earth's crust than iron, the production process of aluminum is much more complex than that of iron. Aluminum is a relatively reactive metal element, and smelting requires electrolysis. The cost of the entire production process is higher than that of iron, so the price of aluminum is also higher than that of iron.
5, Why do soda cans need aluminum cans?
Aluminum cans have the following advantages: they are not easily broken, lightweight, and opaque. The pressure inside soda is higher than normal pressure, and under the action of pressure, aluminum cans are not easily deformed. And aluminum cans can ensure the pressure of carbon dioxide in soda, allowing soda to achieve a better taste effect. Wang Laoji, Babao Congee, etc. use hard iron cans because the packaging is not pressure free and aluminum cans are easy to deform.
