Steel is the most commonly used material in construction, manufacturing and industry. Two of the most commonly used steels are mild steel and carbon steel.
Although both are used for similar purposes, there are several key differences between the two that make them better suited for different applications.
In this article, we will take a closer look at mild steel and carbon steel and explore the differences between them, including their carbon content.mechanical propertiesand production and finishing processes.
Whether you are a metalworker or engineer or just want to understand bettersoft steeland carbon steel, we provide you with all the information you need to make an informed decision.
What is mild steel?
Mild steel is a type of carbon steel with a low amount of carbon (usually 0.05% to 0.25%); these are also known as "low-carbon steel." Low-carbon steel is considered a relatively inexpensive and versatile material that is commonly used in various construction and manufacturing applications.
The low carbon content makes mild steel tougher and easier to shape, form and weld than other steels. Mild steel has good propertiesworkabilityand can be easily drilled, cut and produced in different shapes and sizes.
In addition, low carbon steel has a relatively hightensile strength, making it suitable for use in high voltage applications such as beams, columns and machine parts. Its versatility and affordability make it a popular choice for a wide range of applications.
Read more about mild steelher.
What is carbon steel?
Carbon steel is a type of steel that contains carbon as the main alloying element, while other elements are present in smaller amounts. This metal is widely used in the manufacture of many products and structures due to its high strength and low cost.
Carbon steel can be further classified into different grades based on its chemical composition and mechanical properties, such as low carbon steel (mild steel), medium carbon steel, high carbon steel, and ultra-high carbon steel. Each class has its own specific uses and applications, depending on the desired properties of the final product.
Medium to high carbon steel is often used for the manufacture of machine parts such as gears, crankshafts and shafts. Its high strength and particularly high hardness make it an ideal choice for a wide range of tool applications.
Carbon steel types
There are several types of carbon steel, each with unique properties and applications. These types include:
Low carbon steel
Also known as "mild steel", this type of steel is tougher and easier to shape, form and weld compared to other carbon steels. This makes mild steel a popular choice over higher carbon steels when it comes to structural and manufacturing applications.
Medium carbon steel
Contains a carbon content of 0.3% to 0.6%, making it stronger and harder than low-carbon steel, but also more brittle. It is often used in applications that require both strength and ductility, such as machine parts, automotive parts and building frames.
High carbon steel
High carbon steel contains 0.6% to 1.5% carbon and is known for its high strength and hardness, but high carbon steel is even more brittle than medium carbon steel. High carbon steel is used in applications that require high strength, such as knife blades, hand tools and springs.
Mild Steel vs. Carbon Steel: What's the Difference?
| Comparison | Soft steel | Carbon steel |
| Carbon content | Lav | Medium to ultra high |
| Mechanical force | Moderate | High |
| Ductility | High | Moderate – Low |
| Corrosion resistance | Arm | Arm |
| Weldability | Good | Generally not suitable |
| Cost | Cheap | Slightly higher per weight |
Production process of mild steel and carbon steel
The manufacturing process for mild steel and carbon steel varies depending on the type of steel and the intended qualities of the final product. The production process is often divided into three phases:
- Primary
- Subordinate
- To pour
Primary processes
Steel can be made entirely from recycled material or from a mixture of recycled and virgin steel using the BOF process.
Basic oxygen furnace (BOF)
Mild steel and carbon steel are commonly produced using the Basic Oxygen Furnace (BOF) method, which converts raw materials such as iron ore and co*ke into liquid steel.
The liquid steel is poured into molds for the production of plates or blocks. Pure oxygen is pushed through the liquid steel to oxidize the extra carbon, resulting in a final product with a carbon content of up to 0.5%.
Secondary processes
The market's need for higher quality steel products with more uniform properties stimulated the development of secondary steelmaking processes. This allows manufacturers to alter the carbon content to produce the resulting low-carbon steel, medium-carbon steel, high-carbon steel, or ultra-high-carbon steel.
Electric arc furnace (EAF)
In an electric arc furnace, the steel composition is changed by adding or removing specific components or by manipulating the temperature. EAF processes include:
- Stir– Separation of non-metallic impurities guarantees a hom*ogeneous combination and composition of the steel.
- Bucket oven– Allows precise temperature control and the measured injection of alloy components.
- Ladle injection– Inert gas is injected into the bottom of the steel bath to achieve a stirring effect.
- Degas– Removes hydrogen, oxygen and nitrogen while reducing the sulfur content of the product.
- Adjustment of the composition– Crucial to achieve agitation (in sealed argon bubbling while oxygen is blown — CAS-OB).
Deoxidizing steel
The elimination of oxygen is an important step in secondary steel production. When molten steel begins to solidify, the presence of oxygen causes a reaction with carbon, producing carbon monoxide gas.
Control of deoxidation can be used to change the material properties of the final product and thus the suitability of the steel for various desired applications. Deoxidizing steel processes include:
- Rimming steel– Non-deoxidized or partially deoxidized steels.
- Steel with layer– Originally similar to rimming, but the mold is closed to prevent carbon monoxide formation.
- Half-killed steel– Partially deoxidized and has a carbon content between 0.15 and 0.3%.
- Dead steel– Completely deoxidized to the point where no carbon monoxide is formed during solidification.
To pour
Traditional casting methods involve pouring molten steel into individual molds placed on rail cars. Casting machines allow the continuous pouring of molten steel into molds more suitable for further processing.
Ingots are moved to soak pits to be reheated for hot rolling. In a continuous casting machine, steel is produced for plates, flowers orbats.
Finishing processes of mild steel and carbon steel
The finishing procedure for mild steel and carbon steel can have a significant impact on the appearance and performance of the final product. Carbon steel is finished with:
- Send
- Heat treatment
- Surface treatment
- Downstream secondary treatment
Send
Product roles
Solid cast blocks must be rolled into more usable shapes and sizes, similar to continuously cast blocks. The rollers rotate faster than the steel as it enters the machine, propelling it forward and compressing it.
Hot forming
To break the cast microstructure, steel is heatedrecrystallization temperature. This results in a more uniform grain size and an even distribution of carbon throughout the steel.
Cold forming
Cold forming is performed at temperatures lower than the recrystallization temperature. This procedure improves the finish and increases strength by up to 20% through strain hardening. In a rolling mill, semi-finished products are further processed into intermediate products. They are then ready for the downstream industry to produce and process them.
Heat treatment
The purpose of heat-treated steel is to change the distribution of carbon in the product and its internal microstructure, thereby changing its mechanical properties. When the mechanical properties of the steel change due to heat treatments, an increase in theductilityleads to a decrease in hardness and strength (and vice versa).
Normalization
Steel is heated to approximately 55 °C (130 °F) above the highest critical temperature. The upper critical temperature is maintained until the entire product is evenly heated, after which it is cooled in air. This is the most common form of heat treatment and gives steel exceptional strength and hardness.
Glowing
Steel is heated to a solid solution temperature for one hour before being cooled at a rate of 21°C (70°F) per hour. o'clock. Internal stresses are eliminated, resulting in mild and ductile steel.
Extinction
This is similar to normalizing heat treatment, except that cooling is accelerated by quenching the steel in water, brine, or oil. The resulting material is extremely hard but extremely brittle, making it prone to breakage and cracking.
As a result, for precise control of the steel's properties, this is usually followed by a controlled rate of cooling to room temperature in a process known as tempering orpressure relief.
Surface treatment
About a third of all steel produced has a surface coating to prevent corrosion and increase weldability and paintability.
Hot-dip galvanizing
Galvanizing is the application of a zinc layer to steel. The steel is heated before entering a zinc bath, where liquid zinc covers the surface of the product. Gas knives are used to adjust the layer thickness. A small amount of aluminum is added to the zinc solution to prevent the zinc layer from breaking.
Electrolytic galvanization
Electrolytic galvanizing is another method of applying a zinc coating to steel products. By controlling the current in an electrolyte solution, zinc is deposited on the surface of the steel. This approach allows more precise control of the layer thickness.
For more information on metal finishing options, check out ourvideoblog.
Downstream secondary treatment
Steel raw materials are further processed by downstream companies into the desired end products. Various machining procedures, such as machining and joining, including uniform removal of surface metal by machine tools and welding, are common.
Does carbon steel rust easily?
Carbon steel consists mainly of iron, making it more susceptible to rust. When exposed to humid conditions, carbon steel can corrode and form rust, a reddish-brown iron oxide. This is because the steel reacts with oxygen in the air and produces iron oxide (rust). The same goes for mild steel.
However, the corrosion rate of carbon steel can be affected by several factors, including the environment in which it is used, the presence of other metals or substances that can accelerate corrosion, and the specific type of carbon steel.
Some types of carbon steel may be more resistant to rust than others, and the use of coatings, such as paint or galvanization, can help reduce the risk of rust developing.
Is carbon steel better than mild steel?
Both types of carbon steel have their own unique properties and benefits that make them more suitable for some applications than others. Which one is best usually depends on your specific requirements.
Mild steel is better used for low-stress applications due to its ease of manufacture and low cost, while carbon steel (from medium carbon steel to ultra-high carbon steel) is better used for high-strength applications due to its high carbon content and high carbon content. power.
Carbon steel has a significant strength advantage over mild steel. Carbon steel can be up to 20% stronger than mild steel, making it an excellent choice for high strength applications or where high hardness is required.
One of the main disadvantages of carbon steel is its high cost. Due to the increased carbon content, carbon steel is often more expensive than mild steel.
In addition, carbon steel is more difficult to weld than mild steel, making it less suitable for welding applications.
