What is carbon steel (C-Steel)?
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Written by Dr. Juergen Abrams on July 3, 2024.
Carbon steel (Plain carbon steel) is an iron-carbon alloy with a carbon content range from 0.05% to 2.1% by weight. It contains a maximum of manganese (1.65 wt.%), silicon (0.6 wt.%) and copper (0.6 wt.%). It does not contain significant amounts of other alloying elements, distinguishing it from alloy steels.
C-steel can be divided into Low, Medium, High and Ultra High based on its carbon content. It is known for its high hardness, strength, and resistance to wear.
CLASSIFICATIONS OF CARBON STEEL:
Low Carbon Steel:
Carbon content: 0.05% to 0.25%.
Characteristics: Soft, ductile, and easily weldable.
Uses: Structural shapes, auto body panels, wire products, etc.
Medium Carbon Steel:
Carbon content: 0.25% to 0.6%.
Characteristics: Higher strength and hardness than low carbon steel but less ductile.
Uses: Gears, axles, railway tracks, etc.
High Carbon Steel:
Carbon content: 0.6% to 1.4%.
Characteristics: Very hard and strong, less ductile, and difficult to weld.
Uses: Cutting tools, springs, high-strength wires, etc.
Ultra-High Carbon Steel (UHCS):
Carbon content: 1.25% to 2.1%.
Characteristics: Extremely hard and brittle.
Uses: Specialized applications like knives, axles, and certain machinery parts (non-industrial-purpose).
COMMON GRADES OF CARBON STEEL:
The properties of carbon steels are primarily influenced by the carbon content and the presence of trace amounts of other elements. Common grades of carbon steel are e.g. 1045, 1018, A36 or W1.
Carbon (C): 0.42-0.5%
Silicon (Si): 0.15-0.4%
Manganese (Mn): 0.60-0.80%
Phosphorus (P): ≤ 0.03%
Sulfur (S): ≤ 0.03%
Carbon (C): 0.15 - 0.2%
Silicon (Si): ≤ 0.4%
Manganese (Mn): 0.60-1.2%
Phosphorus (P): ≤ 0.04%
Sulfur (S): ≤ 0.05%
Carbon (C): 0.25 - 0.29%
Silicon (Si): ≤ 0.4%
Manganese (Mn): 0.6-1.2%
Phosphorus (P): ≤ 0.04%
Sulfur (S): ≤ 0.05%
W1 Steel
Carbon (C): 0.9-1.05%
Silicon (Si): 0.1-0.25%
Manganese (Mn): 0.3-0.4%
Phosphorus (P): ≤ 0.025%
Sulfur (S): ≤ 0.025%
Chromium (Cr): ≤ 0.2%
Molybdenum (Mo): ≤ 0.1%
Vanadium (V): ≤ 0.1%
Tungsten (W): ≤ 0.2%
1045 Carbon Steel (C45U)
AISI 1045 carbon steel (C45U) is a medium carbon steel that is widely used in industrial and engineering applications due to its balance of strength, toughness, and wear resistance.
A36 Carbon Steel
AISI A36 carbon steel is one of the most commonly used grades of structural steel. It is a low carbon steel with excellent mechanical properties and good weldability, making it suitable for a wide range of applications.
1018 Carbon Steel
AISI 1018 carbon steel (C18) is a low carbon steel that is widely used in various applications due to its good balance of strength, ductility, and ease of machining and welding.
W1 Carbon Steel (C90U)
AISI W1 carbon steel, also known as C90U steel, is a high carbon steel with excellent hardness and wear resistance, making it suitable for applications requiring high strength and durability. It is suitable for a wide range of applications requiring durable and high-performance materials.
CARBON STEEL CHART
• Hardness
• Surface Hardness
• Yield Strength
![carbon steel chart carbon-steel-chart](https://us.abrams-industries.com/media/wysiwyg/carbon-steel-us-cms-2.jpg)
WHAT IS CARBON STEEL USED FOR?
Carbon steel is used in a wide variety of applications across multiple industries due to its versatile properties. Here are some of the primary uses of carbon steel:
CARBON STEEL FAQ
Carbon Steel vs. Mild Steel
Mild steel, also known as low carbon steel, is a type of carbon steel that contains a relatively low percentage of carbon, typically around 0.05% to 0.25% by weight. This low carbon content gives mild steel several notable characteristics.
Carbon steel vs. low alloy steel
When comparing carbon steel to low alloy steel, there are several key differences in terms of composition, properties, and applications.
AISI Definition of carbon steel
The American Iron and Steel Institute (AISI) defines carbon steel as follows:
Carbon steel is defined as steel that meets the following criteria:
Silicon Content: The maximum content of silicon does not exceed 0.60%.
Copper Content: The maximum content of copper does not exceed 0.60%.
Other Elements: No minimum content is specified for other alloying elements such as chromium, cobalt, molybdenum, nickel, niobium, titanium, tungsten, vanadium, zirconium, or any other element to be added to obtain a desired alloying effect.
What are the disadvantages of carbon steel?
Carbon steel, while widely used and valued for its versatility, has several disadvantages
- Carbon steel is prone to rust and corrosion.
- High and Ultra-High carbon steel can be quite brittle.
- Higher carbon content in steel can make welding more difficult.
- Lower ductility and malleability compared to some other steel alloys.
- Improper heat treatment can lead to undesirable properties.
- Carbon steel with a higher carbon content can be more difficult to machine.
- Carbon steel tends to tarnish and discolor.
In summary, carbon steel has many advantageous properties, including strength, affordability, and availability. Its drawbacks regarding corrosion resistance, brittleness, and other factors should be taken into account when selecting steels for specific applications.
CUSTOMIZED CARBON STEEL
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