- Steel is the alloys of iron and carbon.
- Carbon content should not be in excess of 2%.
- Alloy elements are made of phosphorous, sulfur, oxygen, nitrogen, manganese, silicon, aluminum, copper, nickel etc.
- Steel is wrought, rolled, cast and welded but not extruded.
Different types of alloy components and their objectives :-
- Aluminum is useful for surface solidification.
- Chromium is helpful for resisting corrosion.
- Copper is useful for resisting atmospheric corrosion.
- If manganese is used in small amounts, it is useful for solidification and if used in large amounts; it is useful for wear resistance.
- Molybdenum is mixed with other alloying metals like chromium & nickel to enhance corrosion resistance as well as improve tensile strength devoid of minimizing ductility.
- Nickel can enhance tensile strength devoid of minimizing ductility; in extreme concentrations, enhance corrosion resistance.
- Silicon can reinforce low alloy steels and enhance oxidation resistance, in greater amounts it can offer solid, brittle castings resistance to corrosive chemicals.
- Sulfur is useful for free machining, particularly in mild steels.
- Titanium can resist inter-granular corrosion of stainless steels.
- Tungsten, vanadium, and cobalt are useful for rigidity and erosion resistance.
TYPES OF STEEL
Carbon steel
- Low Carbon Steel
- Medium/mild carbon steel (M.S)
- High-carbon steel
- Ultra-high-carbon steel
Carbon Steel
Carbon steel belongs to unalloyed steel in which the leftover component like carbon, manganese, phosphorus, sulfur and silicon are controlled.
If the carbon content is raised, the stability and rigidity are also increased but the ductility & weldability are reduced.
Alloy steel
- Stainless steel
- HSLA Steel (high-strength low-alloy)
- Weathering Steel
Stainless Steel
It is an alloy steel that comprises of a minimum of 12% of chromium and extra nickel, manganese, molybdenum alloy components.
It has good resistance strength against heat, oxidation & corrosion.
It does not include stain, corrode or rust like ordinary steel but not stain-resistant.
HSLA (High-Strength Low-Alloy) Steel
It is a series of low-carbon steels which include lower than 2% alloys in a chemical composition to enhance strength, ductility & resistance against corrosion.
It has good strength and rigidity as compared to ordinary carbon steel.
Tools Steel
It belongs to different types of carbon and alloy steels which are suitable for being transferred into tools.
It is very strong and has good resistance strength against erosion and deformation as well as capability to retain a cutting edge.
