Steel can be categorized into four basic groups based on chemical compositions:

#1 Carbon Steel

#2 Alloy Steel

#3 Stainless Steel

#4 Tool Steel

There are many different grades of steel that encompass varied properties. These properties can be physical, chemical and environmental. All steel is composed of iron and carbon. It is the amount of carbon and the additional alloys that determine the properties of each grade.

Types of Steel can also be classified by a variety of different factors:

#1 Composition:

Carbon range, Alloy, Stainless.

#2 The production method:

Continuous cast, Electric furnace, Etc.

#3 Finishing method used:

Cold Rolled, Hot Rolled, Cold Drawn (Cold Finished), Etc.

#4 Form or shape:

Bar, Rod, Tube, Pipe, Plate, Sheet, Structural, Etc.

#5 De-oxidation process (oxygen removed from steelmaking process):

Killed & Semi-Killed Steel, Etc.

#6 Microstructure:

Ferritic, Pearlitic, Martensitic, Etc.

#7 Physical Strength (Per ASTM Standards).

#8 Heat Treatment:

Annealed, Quenched & Tempered, Etc.

#9 Quality Nomenclature:

Commercial Quality, Drawing Quality, Pressure Vessel Quality, Etc.

#10 Carbon Steel

Carbon Steel can be segregated into three main categories: Low carbon steel (sometimes known as mild steel); Medium carbon steel; and High carbon steel.

#11 Low Carbon Steel (Mild Steel):

Typically contain 0.04% to 0.30% carbon content. This is one of the largest groups of Carbon Steel. It covers a great diversity of shapes; from Flat Sheet to Structural Beam. Depending on the desired properties needed, other elements are added or increased. For example, Drawing Quality (DQ) – The carbon level is kept low and Aluminum is added, and for Structural Steel the carbon level is higher and the manganese content is increased.

#12 Medium Carbon Steel:

Typically has a carbon range of 0.31% to 0.60%, and a manganese content ranging from .060% to 1.65%. This product is stronger than low carbon steel, and it is more difficult to form, weld and cut. Medium carbon steels are quite often hardened and tempered using heat treatment.

#13 High Carbon Steel:

Commonly known as “carbon tool steel” it typically has a carbon range between 0.61% and 1.50%. High carbon steel is very difficult to cut, bend and weld. Once heat treated it becomes extremely hard and brittle.