Why iron is rusty?

Iron is a metal that is easy to rust. Most of the iron objects displayed in museums are rusted. Vegetable sliced ​​knife if left unused for several months will rust. Every year worldwide millions of tons of steel turn into rusty iron.

Iron is rusted in addition to its chemical activity and also due to external conditions. Water is a condition that causes iron to rust. Chemists have shown that if iron is kept in an atmosphere without water, it will never rust. However, water alone will not cause iron to rust. But if you put iron flakes in a kettle boiling with distilled water in a closed jar, then the iron won't rust.The reason is that only when water and oxygen work together will cause iron to rust. In addition, carbon dioxide dissolved in water also causes iron to rust. The composition of rust is very complex, mainly consisting of iron oxide, iron hydroxide, iron carbonate .

A completely rusted piece of iron will increase the volume about 8 times.

Rust is both porous and soft like a sponge. A completely rusted piece of iron will increase the volume about 8 times. A rusty piece of iron with a sponge-like state will easily absorb water and quickly decay.

There are many factors that make iron susceptible to rust: Like salts dissolved in water, surfaces on iron objects are not clean, roughness, carbon content in steel .

People have devised many measures to prevent iron and rust . The most common method is to coat iron and steel objects with a set of painted and painted "coats" that are simple measures against rust. On the iron bridges for people often painted, in hot air hoses people painted aluminum powder paint, on tin containers, galvanized iron sheets .

The most radical measure to prevent rust is to give iron a "strong core" , which is to add other metals to create stainless steel alloy steel. Inert stainless steel alloy, stainless is due to people have put into the metal nickel, chrome metal into stainless steel.

1. The secret of a 1,600-year-old open-cast iron pillar made of stainless
2. Why copper has so many different colors?