The main difference between mild steel plates and high-carbon steel plates lies in their carbon content: low-carbon steel plates have a low carbon content, so they are softer, have good toughness, strong plasticity, and good welding and processing performance; while high-carbon steel plates have a high carbon content, which leads to a significant increase in hardness and strength, but a decrease in toughness and plasticity, an increase in brittleness, and greater difficulty in welding and processing. This is the fundamental difference between the two in terms of performance and application. Today, we will discuss in detail the differences between mild and high-carbon steel plates.
The main differences between mild steel plates and high-carbon steel plates:
1. Toughness difference: Low-carbon steel plates have a ferrite and a small amount of pearlite microstructure after annealing, resulting in lower strength and hardness, but better plasticity and toughness. Therefore, they have good cold formability and can be cold-formed by methods such as rolling, bending, and stamping. High-carbon steel plates, after appropriate heat treatment or cold drawing hardening, possess high strength and hardness, high elastic limit and fatigue limit, and acceptable machinability, but poor weldability and cold plastic deformation ability.
2. Application difference: Low-carbon steel plates have good weldability. Low-carbon steel with a carbon content of 0.10% to 0.30% is easily processed by various methods such as forging, welding, and cutting, and is commonly used to manufacture chains, rivets, bolts, shafts, etc. High-carbon steel plates are mainly used to manufacture springs and wear-resistant parts. Carbon tool steel is a high-carbon steel with virtually no alloying elements added; it is also a relatively low-cost, well-workable, and widely used type of tool steel.
3. Different carbon content: Low carbon steel plate is carbon steel with a carbon content of less than 0.25%. It has lower strength and hardness, but better plasticity and toughness. High carbon steel plate is often called tool steel. Its carbon content ranges from 0.60% to 1.70%. It has high strength and hardness, high elastic limit and fatigue limit, and acceptable cutting performance, but poor welding performance and cold plastic deformation ability.
4.Chemical Composition and Basic Classification
Low-carbon steel plates refer to carbon steel with a carbon content of less than 0.25%. Due to their low strength, low hardness, and relatively soft texture, they are often called "soft steel." They include most ordinary carbon structural steels and some high-quality carbon structural steels, with an annealed microstructure primarily consisting of ferrite and a small amount of pearlite.
High-carbon steel plates refer to carbon steel with a carbon content between 0.60% and 1.70%, often referred to as tool steel. According to the national standard GB/T699-2015, carbon steel is classified into three main categories based on carbon content: low-carbon steel (≤0.25%), medium-carbon steel (0.25%-0.6%), and high-carbon steel (>0.6%).
It is worth noting that in addition to carbon, both types of steel plates also contain certain amounts of silicon (Si), manganese (Mn), and other elements, while the content of impurity elements such as sulfur (S) and phosphorus (P) is strictly controlled to ensure material performance.
5.Cost and Availability
Mild Steel Plate is generally more economical due to lower alloying content, simpler processing, and widespread availability.
High-Carbon Steel Plate usually has higher material and processing costs because of additional heat treatment and stricter fabrication requirements.
For large-scale projects, mild steel plate often provides the best balance between performance and cost.
6.Different Standards
Mild steel plates commonly correspond to ASTM A36, EN S235JR, and JIS SS400 under different standards.
High-carbon steel plates commonly correspond to ASTM AISI 1095, EN C75/C80, and JIS S75C/S80C under different standards.
Conclusion
Mild steel plate is a versatile, cost-effective material known for its excellent weldability, ductility, and ease of processing, making it ideal for construction and general engineering applications. In contrast, high-carbon steel plate provides superior hardness and strength but requires more careful handling during fabrication. Understanding these differences ensures the correct steel plate is selected for optimal performance and long-term reliability.
The main differences between mild steel plates and high-carbon steel plates:
1. Toughness difference: Low-carbon steel plates have a ferrite and a small amount of pearlite microstructure after annealing, resulting in lower strength and hardness, but better plasticity and toughness. Therefore, they have good cold formability and can be cold-formed by methods such as rolling, bending, and stamping. High-carbon steel plates, after appropriate heat treatment or cold drawing hardening, possess high strength and hardness, high elastic limit and fatigue limit, and acceptable machinability, but poor weldability and cold plastic deformation ability.
2. Application difference: Low-carbon steel plates have good weldability. Low-carbon steel with a carbon content of 0.10% to 0.30% is easily processed by various methods such as forging, welding, and cutting, and is commonly used to manufacture chains, rivets, bolts, shafts, etc. High-carbon steel plates are mainly used to manufacture springs and wear-resistant parts. Carbon tool steel is a high-carbon steel with virtually no alloying elements added; it is also a relatively low-cost, well-workable, and widely used type of tool steel.
3. Different carbon content: Low carbon steel plate is carbon steel with a carbon content of less than 0.25%. It has lower strength and hardness, but better plasticity and toughness. High carbon steel plate is often called tool steel. Its carbon content ranges from 0.60% to 1.70%. It has high strength and hardness, high elastic limit and fatigue limit, and acceptable cutting performance, but poor welding performance and cold plastic deformation ability.
4.Chemical Composition and Basic Classification
Low-carbon steel plates refer to carbon steel with a carbon content of less than 0.25%. Due to their low strength, low hardness, and relatively soft texture, they are often called "soft steel." They include most ordinary carbon structural steels and some high-quality carbon structural steels, with an annealed microstructure primarily consisting of ferrite and a small amount of pearlite.
High-carbon steel plates refer to carbon steel with a carbon content between 0.60% and 1.70%, often referred to as tool steel. According to the national standard GB/T699-2015, carbon steel is classified into three main categories based on carbon content: low-carbon steel (≤0.25%), medium-carbon steel (0.25%-0.6%), and high-carbon steel (>0.6%).
It is worth noting that in addition to carbon, both types of steel plates also contain certain amounts of silicon (Si), manganese (Mn), and other elements, while the content of impurity elements such as sulfur (S) and phosphorus (P) is strictly controlled to ensure material performance.
| Property | Mild Steel Plate | High-Carbon Steel Plate |
| Carbon Content | 0.05%–0.25% | 0.60%–1.00%+ |
| Tensile Strength | Moderate | High |
| Hardness | Low | Very High |
| Ductility | Excellent | Limited |
| Toughness | High | Lower |
| Weldability | Excellent | Poor to Moderate |
| Formability | Very Good | Poor |
5.Cost and Availability
Mild Steel Plate is generally more economical due to lower alloying content, simpler processing, and widespread availability.
High-Carbon Steel Plate usually has higher material and processing costs because of additional heat treatment and stricter fabrication requirements.
For large-scale projects, mild steel plate often provides the best balance between performance and cost.
6.Different Standards
Mild steel plates commonly correspond to ASTM A36, EN S235JR, and JIS SS400 under different standards.
High-carbon steel plates commonly correspond to ASTM AISI 1095, EN C75/C80, and JIS S75C/S80C under different standards.
Conclusion
Mild steel plate is a versatile, cost-effective material known for its excellent weldability, ductility, and ease of processing, making it ideal for construction and general engineering applications. In contrast, high-carbon steel plate provides superior hardness and strength but requires more careful handling during fabrication. Understanding these differences ensures the correct steel plate is selected for optimal performance and long-term reliability.
