In this article, you will know the different types of steel as well as their properties, uses, advantages and disadvantages.
Steel is an alloy of iron and carbon, with small amounts of other elements.
It is a strong, durable material that is widely used in construction, automotive manufacturing, and a variety of other industries.
Steel is known for its high tensile strength, which makes it resistant to breaking under tension.
It is also highly resistant to wear and corrosion, which makes it a popular choice for a wide range of applications.
The properties of steel can be adjusted by controlling the amount of carbon and other elements that are present in the alloy, as well as by using different manufacturing techniques.
So without wasting time let's get started.
What is Steel?
Steel is mainly a mixture of iron and carbon.
Steel is composed of iron and carbon. The carbon content in steel can range from 0.1-1.5%, but the most widely used grades of steel contain only 0.1-0.25% carbon.
To get some special properties, other metals are also added to it.
Elements such as manganese, phosphorus, and sulfur are found in all grades of steel, but, whereas manganese provides beneficial effects, phosphorus and sulfur are deleterious to steel's strength and durability.
Types of Steel
Steel is mainly divided into the following types:
- Carbon Steel
- Alloy Steel
Carbon Steel
The steel whose main components are iron and carbon is called carbon steel.
It is also called plain steel.
Carbon steel is probably used for at least 80% of all components in refineries and petrochemical plants because it is inexpensive, readily available, and easily fabricated.
According to the percentage of carbon in iron, carbon steel is divided into three parts:
- Low Carbon Steel
- Medium Carbon Steel
- High Carbon Steel
 |
| Different Types of Steel |
Low Carbon Steel
The amount of carbon in low-carbon steel ranges from 0.15% to 0.25%.
It is also called mild steel.
Due to the low carbon content, it is soft.
Parts made from it cannot be hard and tempered but they can hard case.
It is used for making nuts, bolts, sheets, wires, machine parts, rods, etc.
Medium Carbon Steel
The amount of carbon in medium carbon steel ranges from 0.25% to 0.6%.
It is harder and tougher than mild steel, and its tensile strength is also high.
Its hardening and tempering can be done.
It is used to make gears, agricultural implements, shafts, spindles, camshafts, spanners, connecting rods, etc.
High Carbon Steel
The carbon content in high-carbon steel ranges from 0.6% to 1.5%.
It is very hard, due to which it wears less.
It can be hardened.
It is used in making sharp tools, dies, punches, files, chisels, and other cutting tools.
Advantages of Carbon Steel
There are the following advantages of carbon steel:
- Carbon steel is stronger than many other types of steel, thanks to its high carbon content. This makes it ideal for use in construction, where strength and durability are important.
- Carbon steel is generally less expensive than other types of steel, due to its lower levels of alloying elements.
- It is relatively easy to weld, making it a popular choice for many manufacturing applications.
- It can be heat-treated to increase its hardness and strength, making it ideal for use in applications where high wear resistance is required.
- It can be used in a wide range of applications, including structural steel, automotive components, and machinery parts. It is also widely used in the production of pipes, tubes, and other hollow structural sections.
- It is highly recyclable, making it an environmentally friendly choice for many applications.
Disadvantages of Carbon Steel
There are several disadvantages to using carbon steel:
- Carbon steel is prone to rusting and corrosion, especially in damp or humid environments. This can reduce its lifespan and make it less durable.
- While carbon steel can be coated or treated to improve its corrosion resistance, it is generally not as corrosion-resistant as other types of steel or other metals.
- This steel is not as wear-resistant as some other types of steel, such as stainless steel or tool steel. It may not be suitable for applications that require high levels of wear resistance.
- This steel is not as ductile as some other types of steel, which means it is not as flexible or malleable. This can make it more difficult to work with and shape.
- It may not be suitable for high-temperature applications because it can lose strength and become brittle at high temperatures.
- Carbon steel is not as impact-resistant as some other types of steel, which means it may not be suitable for applications that require high levels of impact resistance.
Alloy Steel
The steel in which some special properties are obtained by adding other metals like nickel, chromium, vanadium, manganese, molybdenum, tungsten, etc is called alloy steel.
Types of Alloy Steel
Alloy steel can be classified into the following types:
- Low Alloy Steels
- High Strength Low Alloy Steels
- High Alloy Steel
- High-Speed Steel
- Tool Steel
- Free Cutting Steels
- Maraging Steels
- Low Expansion Steels
- Nickel Steel
- Nickel Cobalt Steel
- Nickel Chrome Steel
- Vanadium Steel
- Manganese Steel
- Silicon Steel
- Cobalt Steel
- Molybdenum Steel
- Stainless Steel
Low Alloy Steels
They have similar microstructures and require similar heat treatments to that of plain carbon steels.
When Nickel, chromium, molybdenum, and other alloying elements consist of less than 10.5% by the weight they are defined as low alloy Steel.
For example cr-mo steel, Ni steel, weathering steel, etc.
High Strength Low Alloy Steels
It is also referred to as micro-alloyed steel.
They have the addition of elements such as Al, Nb, and V either singly or in combination.
It contains 0.07 to 0.13% carbon with 0.5% Aluminium.
These steels show good ductility, malleability, formability toughness, and weldability because their strength increases up to 50- 80 Kg/mm² and is widely used in the automotive industry.
High Alloy Steel
When alloying content of more than 10.5% by weight is called high alloy steel.
They are costly and special-purpose alloys of steel.
For example stainless steel, high-speed steel, etc.
High-Speed Steel
High-speed steel is made by adding tungsten to steel, hence it is also known as tungsten steel.
Tungsten steel is very hard and maintains its hardness even at high temperatures.
It is used in making cutting tools, drill bits, hex blades, cutters, reamers, etc.
According to the amount of tungsten, it is of three types:
- Super High-Speed Steel
- Medium-High Speed Steel
- Low High-Speed Steel
Super High-Speed Steel
It contains 22% tungsten, chromium 4%, and vanadium up to 1%.
Medium-High Speed Steel
It contains tungsten 18%, chromium 4%, and vanadium 1%.
Low High-Speed Steel
It contains tungsten 14%, chromium 4%, and vanadium 1%.
Tool Steel
They are tungsten alloyed Steel containing about 0.7 % of carbon, 18% of tungsten, 4% of chromium, and 1% of vanadium.
The alloying elements like tungsten, chromium, and vanadium form carbides which leads to the high hardness of tool steel.
Tool steel is special Steel that is well suited for making mechanical tools like drills, saw blades, etc.
Free Cutting Steels
These steels can be machined or cut with fast speed because of their high machinability and are hence known as free-cutting steels.
Low-carbon steels produce rough surfaces and are responsible for heating the tool, So Mg, S, and P are added to improve machinability.
Mg combines with S and favors chip formation and also increases hardness and strength.
Maraging Steels
Maraging steels are steels, which are known for possessing superior strength and toughness without losing malleability, although they cannot hold a good cutting edge.
These steels contain 0.03% C, 18.25% Ni, 3 to 5% Mo, 3 to 8% Co, 0.2 to 1.6% Ti and a small amount of Al.
This steel shows strength up to 210Kg/mm² and is used for special applications such as rockets, engine components,s and pressure vessels.
Due to the low carbon content maraging steels have good machinability and offer good weldability.
Due to the high alloy content, maraging steels have a high hardenability.
Low Expansion Steels
These are the alloys of nickel and iron containing 36% Ni, 02% C, 0.5% Mn and balance iron.
These steels have a very low coefficient of expansion and it is widely used for application such as gauges, tapes, and micrometers.
corrosion-resistant.
It does not rust.
It cannot be hardened.
It is often used to make household utensils, watch parts, automobile parts, cars, knives, and airplanes.
Nickel Steel
It contains up to 4% nickel metal.
Its hardness, elastic limit, and tensile strength are high and it does not rust easily.
It is used in making rivets, pipes, axles, and parts of aircraft and engines.
Nickel Cobalt Steel
If 30% to 35% nickel and 5% cobalt are added to the steel, it is called nickel-cobalt steel.
It is also called Invar steel.
Its coefficient of expansion is very less that's why it is used as a precision instrument.
Nickel Chrome Steel
The steel in which 0.5% to 1% carbon, 0.3% to 0.8% manganese, 3% to 5% nickel, and 0.5% to 1.8% chromium are mixed is called nickel chrome steel.
This increases the elastic limit, reduces wear, and also increases hardness and tensile strength.
It is used in making cutlery, automobile parts, cutting tools, etc.
Vanadium Steel
The steel in which 1.5% carbon, 12.5% tungsten, 4.5% chromium, 5% cobalt, and 5% vanadium is added is called vanadium steel.
Due to this, its elastic limit and tensile strength increase, and the ability to tolerate strong shocks arise.
It is mostly used for making tools and cutters.
Manganese Steel
The steel in which 1.0% to 1.9% manganese, and 0.4% to 0.8% carbon are mixed is called manganese steel.
It is also called special high alloy steel.
It wears less.
It is used in making rail lines, grinders, etc.
Silicon Steel
Silicon is mixed in this steel in varying amounts from 1% to 14% according to the work.
It is heat resistant.
It does not rust.
Cobalt Steel
The steel which contains 0.5% to 1.5% high carbon and 5% to 35% cobalt is called cobalt steel.
It has more toughness, tensile strength, and magnetic properties, so it is mostly used for making permanent magnets and more sharp tools.
Molybdenum Steel
The amount of molybdenum in it is very heavy.
It contains molybdenum 4.5% to 9%, carbon 0.8 to 1.5%, chromium 4%, and vanadium 1 to 5%.
On mixing these metals in it, a lot of hardness and toughness come.
It is used to make bearings, motor vehicles, airplanes, etc.
Stainless Steel
If nickel 8%, chromium 18%, molybdenum 2%, and carbon 0.2 to 0.6% are mixed in steel, then it is called stainless steel.
Stainless steels generally contain more than 10% chromium as the main alloying element and are valued for high corrosion resistance. It does not stain, corrode or rust as easily as ordinary steel that's why it is called stainless steel.
Stainless steels have a sufficient amount of chromium present so that a passive film of chromium oxide forms which adheres to the metal surface very tightly and prevents further corrosion.
It is very hard, tough, acid-resistant, and corrosion-resistant.
It does not rust.
It cannot be hardened.
It is often used to make household utensils, watch parts, automobile parts, cars, knives, and airplanes.
These stainless steels can be divided into three groups based on their crystalline structure:
- Austenitic Stainless Steel
- Ferritic Stainless Steel
- Martensitic Stainless Steel
Austenitic Stainless Steel
It contains 18-26% chromium (Cr) and 8-22% nickel (Ni) and less than 0.8% carbon.
It is non-magnetic and non-heat-treatable.
Ferritic Stainless Steel
It contains trace amounts of nickel, 12-17% chromium, and less than 0.2% carbon, along with other alloying elements, such as molybdenum, aluminum, or titanium.
These magnetic steels cannot be hardened by heat treatment but can be strengthened by cold working.
Martensitic Stainless Steel
It contains 11-17% chromium, less than 0.4% nickel, and up to 1.2% carbon.
These are magnetic and are similar in composition to the ferritic group but contain higher carbon and lower chromium to permit hardening by heat treatment.
Advantages of Alloy Steel
There are the following advantages of alloy steel:
- Greater strength at elevated temperatures.
- High hardenability.
- Improved ductility and cracking.
- Higher elastic ratio and endurance strength.
- Better machinability at high hardness.
- Less internal stresses.
Disadvantages of Alloy Steel
There are the following disadvantages of alloy steel:
- Higher cost than plain carbon steel.
- Care should be taken during handling.
- Certain grades show temper brittleness.
- Tendency to have retained austenite.
So here you have to know all aspects related to types of steel.
If you have any doubts then you are free to ask me by mail or on the contact us page.
Thank You
0 Comments