Carbon steel is an iron-carbon alloy with a carbon content of up to 2.1% of the steel’s overall weight. It is one of the major classifications of steel, comprising as much as 90% of steel manufactured worldwide. The overarching category of carbon steel can be further broken down into five sub-categories:
- Ultra-low-carbon steels: less than 0.015% carbon;
- Extra-low-carbon steels: between 0.015% and 0.05% carbon;
- Low-carbon steels: between 0.05% and 0.19% carbon;
- Medium-carbon steels: between 0.2% and 0.49% carbon;
- High-carbon steels: a carbon content over 0.5%.
These must all contain less than: 0.6% copper; 0.6% silicon; and 1.65% manganese to qualify as carbon steel, and are each uniquely suited to different applications and technical specifications.
Carbon steel combines the malleability of iron with the high strength of carbon. Although it is initially brittle, carbon steel can be heat-treated into a formable state for the formation of bespoke shapes and plates. It maintains its high toughness and tensile strength throughout heat treatment processes, but its surface layer will subsequently be susceptible to corrosive elements, such as weathering and oxidization.
The problem of weathering and corrosion can be circumvented through carburization processes designed to harden the exterior of the carbon steel, by encouraging carbon migration to the surface of the carbon steel component. The distribution of carbon throughout the steel will be skewed, with a higher carbon density at the surface and a harder, more iron-dense core in the interior. This gives the finished product a unique combination of a wear-resistant skin with a tough core.
Carbon Steel Applications
Due to its high versatility, carbon steel has far-reaching applications, and has been implemented pervasively in a range of industries, particularly the oil, gas, and petrochemical sectors.
As global suppliers of a range of steel products, Masteel have sourced and manufactured carbon steel for a broad range of market sectors, with a specialization in the fabrication of low pressure vessels and industrial boilers for some of the world’s leading fossil fuel energy providers.
Carbon Steel Products from Masteel
Masteel supplies a range of carbon steel products with ASTM, ASME, and EN specifications, with a range of carbon steel grades suitable for fabrication in industrial boilers, pressure vessels, and heat exchangers. These comprise excellent notch toughness with tensile strengths ranging from 60-80 ksi, to 70-90 ksi.
We also supply hydrogen induced cracking (HIC) resistant carbon steel plates with high durability and performance to combat issues of hydrogen and stress-related corrosion in petrochemical pressure vessels and boilers – particularly in sour service environments.