As we all know, there are many types of steel on the market today. Common carbon steel and stainless steel are similar in appearance, making it difficult to distinguish them. So what is the difference between carbon steel and stainless steel?
1.Carbon steel
When people talk about carbon steel, they usually mean high-carbon steel used for knives and tools. High-carbon steels are very hard, which makes them very good at resisting wear and retaining their shape. They can withstand a lot of force before they deform. Unfortunately, hard metals are also brittle: when placed under extreme tensile stress, high-carbon steel is more likely to crack than bend.
Low-carbon steel is more common than high-carbon steel because ① it is less expensive to produce, ② it is more ductile, and ③ it is easier to manufacture. Low-carbon steel tends to deform rather than break under stress, and this ductility makes low-carbon steel easy to machine and weld. They are often used in automotive body panels, bolts, clamps, seamless pipes, and steel plates.
2.Stainless steel
Stainless steel is used in chemical plants and food plants because it can function in humid environments without rusting.
Stainless steel contains iron, carbon, and at least 10.5% chromium. Chromium is key – it reacts with oxygen to form a passivation layer that protects the steel from corrosion. This protection reduces the likelihood of stainless steel rusting – which is important for outdoor furniture (such as bollards) installed in humid environments. The higher the chromium content, the better the corrosion resistance.
3.Carbon steel vs stainless steel
(1) Different appearance
Stainless steel is composed of chromium, nickel and other metals, so stainless steel has a bright silver appearance, a smooth surface and a very good gloss. Carbon steel is an alloy of carbon and iron, so the color of carbon steel is gray and the surface is rougher than stainless steel.
(2) Different corrosion resistance
Both carbon steel and stainless steel contain iron, and it is known that iron will slowly oxidize when exposed to the environment, causing rust on the surface. But stainless steel has chromium added, and chromium combines with oxygen more than iron. As long as chromium is on oxygen, it will form a chromium oxide layer, which can directly protect the steel from degradation and corrosion. Carbon steel also has a lower chromium content, so a small amount of chromium cannot form a chromium oxide layer, so stainless steel has better corrosion resistance than carbon steel.
(3) Different wear resistance
Carbon steel is harder than stainless steel, but it is heavier and less ductile. Therefore, in terms of wear resistance, carbon steel is much more wear-resistant than stainless steel.
(4) Different prices
In the process of making stainless steel, a certain amount of other alloys must be added, but carbon steel does not add a large amount of other alloys, so the price of stainless steel is much more expensive than carbon steel. For example, the price of stainless steel plate is higher than that of carbon steel plate.
(5) Different ductility
Stainless steel has better ductility than carbon steel, mainly because the nickel content in stainless steel is relatively high, and the ductility of these elements is also better, so the ductility of stainless steel is also better. Carbon steel contains less nickel, which can be directly ignored, but the ductility is poor.
