Steel is one of the most versatile of all materials. It can be engineered to meet hardness, strength, ductility and temperature conditions unique to your particular application. Of course, various grades of steel have different machining characteristics. Below is a description of the major classifications.
Low carbon steel: Carbon content less than .20 percent. Tensile strength (annealed) ranges from 40,000 to 70,000 pounds per square inch.
Medium carbon steel: Carbon content from .20 to .50 percent. The tensile strength (annealed) ranges from 65,000 to 105,000 pounds per square inch.
High carbon steel: Carbon content of more than .50 percent. The tensile strength (annealed) ranges from 95,000 to 125,000 pounds per square inch.
Stainless steel is designed to resist atmospheric corrosion, the effects of hot or cold acids and scaling at elevated temperatures. There are two groups of stainless: (1) Corrosion resistance is required, including resistance to high temperature oxidation; (2) Greater mechanical properties of hardness, strength, toughness or ductility are required, including resistance to wear and abrasion.
These grades of stainless have Chromium added from 11% to 17% as the only major alloy. This is the same as the ferritic grades. 0.10% to 0.65% Carbon is added to enable hardening by heat treatment.
Duplex & Super Duplex steels combine corrosion resistance with high mechanical strength. Duplex steels deliberately introduce nitrogen in order to improve ductility and corrosion resistance. This class of steel offers excellent castability, weldability and machinability. 22% Chromium stainless steels provide better pitting resistance and resistance to crevice corrosion than more common type 316 stainless steel and they also have greater mechanical strength. However, for optimum corrosion resistance, a 25% Chromium high alloy Duplex stainless steel is required and these alloys are often referred to as Super Duplex stainless.
Austenitic steels have high ductility, low yield stress and relatively high ultimate tensile strength, compared to typical carbon steel. High percentages of alloys such as Manganese and Nickel are austenitic at room temperature, therefore this steel can only be work-hardened. Austenitic steels are non-magnetic.
Low temperature steel is designed for use in arctic climates for construction, petrochemical and marine industries, where impact resistance and tolerance to subzero conditions is necessary.