Most people think that steel is just a pre-set combination of iron and carbon, but did you know there are more than 3,500 different grades of steel? You can compare steel grades by measuring the amount of carbon, additional alloys, and how the manufacturer processes them.
The Four Types of Steel
Authorities grade and categorize steel types into four groups — Carbon, Alloy, Stainless, and Tool. So what are these different types of steel made of, and what are they used for?
Carbon Steels
Carbon steels only contain trace amounts of elements besides carbon and iron. This group is the most popular of the four grades of steel and it accounts for 90% of steel production.
Carbon Steel has three main subgroups depending on how much carbon is in the metal: Low Carbon Steels/Mild Steels (up to 0.3% carbon), Medium Carbon Steels (0.3–0.6% carbon), and High Carbon Steels (more than 0.6% carbon).
Companies often manufacture these steels in massive quantities since they’re cheap to manufacture and they’re strong enough to use in large-scale construction.
Alloy Steels
Alloy steels are created by adding additional alloying elements like nickel, copper, chromium, and/or aluminum. Incorporating these elements enhances the steel's strength, ductility, corrosion resistance, and machinability.
Stainless Steels
Stainless steels contain 10-20% chromium as their alloying element, as well as other elements such as nickel, silicon, manganese, and carbon.
These steels have remarkably high corrosion resistance and are safe to use in outside construction because they have an increased ability to withstand rough weather. They are also widely utilized in electrical equipment. 304 Stainless Steel, for example, is highly sought after for its ability to withstand the elements while keeping electrical material out of harm's way.
While different grades of stainless steel like 304 Stainless Steel have a place in construction, a majority of industries use stainless steel for their sanitary properties. These steels are commonplace in medical equipment, piping, cutting tools, and food processing equipment.
Tool Steels
Tool steels, as you can probably guess by the name, excel in cutting and drilling equipment. The secret is the tungsten, molybdenum, cobalt, and vanadium that increases their heat resistance and overall durability. And since they retain their shape under heavy usage, they're the go-to material for most hand tools.
What are the different grades of steel?
Steel grading systems give us a way to categorize steel types based on all the different uses that make them distinct.
For instance, the rate that manufacturers cool steel can impact how strong it is on a molecular level. The amount of time they keep steel at critical temperatures during the cooling process plays an important role as well. In fact, it's possible for two sheets of steel with the same alloy content to have different grades based on their heat-treatment process.
- The ASTM Grading System assigns each metal a letter prefix based on its overall category (“A” is the designation for iron and steel materials), as well as a sequentially assigned number that corresponds with that metal’s specific properties.
- The SAE Grading System uses a four-digit number for classification. The first two digits denote the steel type and alloying element concentration, and the last two digits indicate the carbon concentration of the metal.
Steel grading standards are widely used by scientists, engineers, architects, and government agencies to ensure the quality and consistency of materials. These standards provide a common language to communicate the properties of steel with great specificity, and guide product manufacturers toward proper processing and application procedures.
Mead Metals Makes the Grade
Mead Metals supplies steel at the highest SAE grading standards so you can be sure that your material is durable and long-lasting. No matter your industry or order size, we can provide the right type of steel for your unique project. Contact us to get a quick quote today.
FAQs
Authorities grade and categorize steel types into four groups — Carbon, Alloy, Stainless, and Tool.
What are the different types of steels? ›
The Four Types of Steel
Steel is a combination of two elements, iron and carbon. Steel are broken is broken into four types and then in those types steel is broken down into grades. There are four main types of steel, Carbon Steels, Alloy Steels, Stainless Steels, Tool Steels.
How different grades of steel are made? ›
The different steel classifications are based on how they're composed. Iron can be combined with carbon and a wide variety of other elements, creating steels that include carbon steel, stainless steel, alloy steel, and tool steel. Below, we will break down each one and its uses.
What are the 4 types of steel? ›
The four main types of steel include carbon steel, stainless steel, alloy steel, and tool steel. Learn how the different kinds of steel are categorized and how each type can work for your project requirements.
What are the grades of steel in the US? ›
The most common steel grades in the USA for structural steel are ASTM A36, A572, A588, A992, A500, and A709.
Which steel grade is best? ›
Most stainless steel ordered around the world is Grade 304. It offers the standard corrosion resistance, formability, strength, and easy maintenance for which stainless is known. While 316 comes in second in terms of quantities sold, it offers vastly superior corrosion resistance to chlorides and acids.
What grade is the strongest steel? ›
The steel with the highest tensile strength is probably music grade steel wire, also called aircraft wire. ASTM A228 for example. This is a medium to high carbon steel usually with small amounts of manganese and silicon.
What grade of steel is most common? ›
Low carbon steel (or “mild carbon steel” or “plain carbon steel”) refers to carbon steels that have up to 0.30% carbon content. This is, by far, the most common type of steel on the metals market. There are a few reasons for this. For starters, low carbon steel is relatively inexpensive.
What is the cheapest type of steel? ›
Mild steel, also known as low-carbon steel, is a popular material used for a range of applications. It is inexpensive and readily available, making it a preferred choice for many manufacturers.
How are the types of steel different? ›
Alloy steel with 1-5% alloying elements is considered low alloy, while high alloy steel contains 5-50% alloying elements by composition. The benefits of alloy steel include increased strength, wear resistance, toughness, and hardness.
Steel comes in a small range of colors, but you can still get a sense of what metal you have by looking at it. Carbon steel, used in pipes and buildings, is a dark brown color. Stainless steel, used in kitchens, is silver and shiny. In addition, reddish rust spots are an indication that the metal is steel.
What is grade 100 steel? ›
Grade 100 Steel is a high strength low alloy (HSLA) steel containing low amounts of carbon (. 10 max), phosphorous (. 025) and sulfur (. 006) resulting in a cleaner, more hom*ogeneous material.
What is grade 50 steel? ›
Grade 50 steel is a high-strength low alloy steel with a minimum yield strength of 50 ksi and minimum tensile strength of 65 ksi. Grade 50 contains more alloying elements than a plain carbon steel and has a greater resistance to atmospheric corrosion.
What does Grade 60 steel mean? ›
Grade 60 rebar offers a minimum yield strength of 60,000 pounds per square inch, or 420 megapascals on the metric grading scale. It also features a continuous line system, with one line running along the length of the bar which is offset a minimum of five spaces from the center.
What do the numbers in 1018 steel mean? ›
The last two digits indicate that the carbon concentration is 0.01%. For instance, SAE 1018 indicates non-modified carbon steel containing 0.18% of carbon. SAE 5130 indicates a chromium alloy steel containing 1% of chromium and 0.30% of carbon.
What is 1018 steel good for? ›
1018 is considered one of the best choices for carburized parts due to its response to case hardening, making it suitable for applications that need better surface hardness. It offers a good balance of toughness, strength, and ductility, making it versatile for various engineering and structural applications.
Which grade steel is best? ›
Most stainless steel ordered around the world is Grade 304. It offers the standard corrosion resistance, formability, strength, and easy maintenance for which stainless is known. While 316 comes in second in terms of quantities sold, it offers vastly superior corrosion resistance to chlorides and acids.
What grade of steel is the strongest? ›
These additions increase hardenability, corrosion resistance, toughness, and resistance to temperature fluctuations. Two of the strongest grades of steel are EN24T and T45 which are widely used across engineering, aeronautics, and motor sport due to their reliable mechanical properties.
Steel grading systems give us a way to categorize steel types based on all the different uses that make them distinct.
