Carbon Steel vs. Low Carbon Steel

Attribute	Carbon Steel	Low Carbon Steel
Carbon Content	Higher	Lower
Strength	Higher	Lower
Ductility	Lower	Higher
Hardness	Higher	Lower
Weldability	Lower	Higher

Composition

Carbon steel is an alloy that is made up of a combination of iron and carbon. The carbon content in carbon steel typically ranges from 0.06% to 1.5%. On the other hand, low carbon steel, also known as mild steel, has a lower carbon content, usually around 0.05% to 0.25%. This lower carbon content makes low carbon steel more ductile and malleable compared to carbon steel.

Strength

Carbon steel is known for its high strength and hardness, making it ideal for applications that require durability and wear resistance. On the other hand, low carbon steel is not as strong as carbon steel but is more easily formed and welded. Low carbon steel is often used in applications where flexibility and ease of fabrication are important.

Hardness

Due to its higher carbon content, carbon steel is harder and more resistant to abrasion compared to low carbon steel. This makes carbon steel a popular choice for tools, knives, and machinery parts that require a high level of hardness. Low carbon steel, on the other hand, is softer and more easily machinable, making it suitable for applications that do not require high hardness.

Weldability

Carbon steel is more difficult to weld compared to low carbon steel due to its higher carbon content. The presence of carbon can lead to the formation of brittle areas in the heat-affected zone during welding, which can compromise the integrity of the weld. Low carbon steel, on the other hand, is easier to weld and does not require preheating or post-weld heat treatment in most cases.

Corrosion Resistance

Carbon steel is susceptible to corrosion, especially in environments with high moisture or exposure to chemicals. To improve its corrosion resistance, carbon steel can be coated with protective layers such as paint or galvanization. Low carbon steel, on the other hand, has better corrosion resistance due to its lower carbon content. However, it is still susceptible to rust and may require additional protection in corrosive environments.

Cost

Carbon steel is generally more expensive than low carbon steel due to its higher carbon content and the additional processing required to achieve its desired properties. The higher strength and hardness of carbon steel make it a preferred choice for applications where durability is crucial, despite the higher cost. Low carbon steel, on the other hand, is more cost-effective and is commonly used in construction, automotive, and manufacturing industries where high strength is not a primary requirement.

Applications

Carbon steel is commonly used in the production of tools, knives, machinery parts, and structural components that require high strength and hardness. Its durability and wear resistance make it suitable for heavy-duty applications in industries such as construction, mining, and manufacturing. Low carbon steel, on the other hand, is used in a wide range of applications, including automotive body panels, pipes, wire, and sheet metal, where flexibility and ease of fabrication are important.