Steel

Steel triangle
MFA # 17.2048a

Description

16th c. steel daggar
MFA# 16.253

York Flats
MFA # 1981.285

Phase diagragm of iron-carbon

Steel beads

A high-strength Iron alloy containing not more than 2% Carbon. Steel may also contain small amounts of Phosphorus, Sulfur, Manganese, Silicon, Aluminum, Titanium, Copper, Molybdenum, and Nickel. Small amounts of steel were made into swords and cutting implements in antiquity in Japan and India. From 1855-1875, Bessemer, Kelly, Thomas, Gilchrist, Mushet and others developed manufacturing procedures to quickly and consistently produce good quality steel from pig iron. Steel, with its strength, resilience, hardness and formability was being produced in quantities of 25 million tons a year by the end of the 19th century. It was primarily used for construction of ships, bridges, building and skyscrapers. Steel was also used for smaller items, such as knives, weapons, decoration and architectural components (grilles, doors, windows, roofing, gutters, brackets, wire cloth, cables and hardware).

	Composition	Properties	Applications
Carbon steel	Primarily iron and carbon, with carbon content typically up to 2.5%.	Most common type of steel making up 90% of steel production; easily welded or machined; high strength and hardness; more prone to rust and corrosion.	Construction, automotive components, tools, and various industrial applications; they are often galvanized or electroplated with zinc for protection from rust
	Low carbon steel or mild steel: up to 3 % carbon	low cost and easy to form; excellent ductility, weldability, and malleability,	ideal for structural applications and everyday products; machinery, pipes, wires and structural components.
	Medium carbon steel:0.31-0.6% carbon and 0.31-1.6% magnesium	higher strength but lower ductility, making it harder to form than mild steel	automotive components and machinery parts; gears, cranks and machinery parts
	High carbon steel: 0.61-1.50% carbon and 0.31-0.9% magnesium	significantly harder and stronger; less ductile and more difficult to form or weld	commonly utilized in cutting tools and high-strength wires; steel plates and bars
	Added elements	Properties	Applications
Alloy steel	Carbon steel with alloyed elements	More expensive; alloys add enhanced strength, ductility, corrosion resistance, and machinability	Girders, rails, rods, pipelines, and other applications where specific properties are needed
	manganese, silicon, aluminum	remove dissolved oxygen, sulfur and phosphorus
	manganese, silicon, nickel, copper	form solid solution of ferrite
	chromium, vanadium, molybdenum, tungsten	form second phase carbides
	nickel, copper	increase corrosion resistance
	manganese sulfide, lead, bismuth, selenium, tellurium	increase in machinability
	molybdenum	increases embrittlement resistance
	Composition/Structure	Properties	Applications
Stainless steel	Carbon steel with a minimum of 10.5% chromium, which forms a protective oxide layer, preventing rust and corrosion	The added chromium protects the metal from oxidation and corrosion and provides shiny finish, and good strength	Kitchenware, sheet metal, outdoor construction, and applications requiring resistance to harsh environments such as sheet metal and outdoor construction
	Austenitic: face-centered cubic structure that is densely packed	non-magnetic and the most common stainless steel	often used in kitchen appliances.
	Ferritic: body-centered cubic structure that is loosely packed	magnetic and less expensive than most stainless steel
	Martensitic: body-centered tetragonal structure	greater strength but less resistance to oxidation than most stainless steel	used in pliers, cutlery and medical instruments
	Processing / Series identification	Properties	Applications
Tool steel	Carbon and Alloy steels containing elements like cobalt, molybdenum, tungsten, and vanadium for enhanced hardness and wear resistance	High hardness, durability, and ability to hold a sharp edge	Cutting tools, dies, molds, and other applications requiring high strength and wear resistance
	Water-hardening (series W)	high hardness and lower cost but tend to be brittle and unsuited for high temperatures	drills, cutlery
	Cold Work: Air hardening (series A); oil-hardening (series O)	have high wear resistance and toughness	many types of dies, bushings, gauges; knives; cutting tools, woodworking tools
	Hot-work (series H)	retain their hardness and strength at high temperatures	saw blades, drill bits router bits
	Shock resisting (series S)	effective at low and high temperature but are less corrosion resistant	chisels, breakers, hammers, and neumatic tools

Synonyms and Related Terms

acier (Fr.); Stahl (Deut.); acero (Esp.); staal (Ned.); aço (Port.)

Brand names: See also Cor-Ten,

Risks

Inhalation of dust or metal fumes is dangerous.

Resources and Citations

• G.S.Brady, Materials Handbook, McGraw-Hill Book Co., New York, 1971 Comment: p. 771
• Ralph Mayer, A Dictionary of Art Terms and Techniques, Harper and Row Publishers, New York, 1969 (also 1945 printing)
• Thomas C. Jester (ed.), Twentieth-Century Building Materials, McGraw-Hill Companies, Washington DC, 1995
• Tom Rowland, Noel Riley, A-Z Guide to Cleaning, Conserving and Repairing Antiques, Constable and Co., Ltd., London, 1981
• Michael McCann, Artist Beware, Watson-Guptill Publications, New York City, 1979
• Dictionary of Building Preservation, Ward Bucher, ed., John Wiley & Sons, Inc., New York City, 1996
• Ivan Amato, Stuff: The Materials the World is Made of, Avon Books, New York, 1997 Comment: p. 46
• Wikipedia: Steel Accessed March 2025