Nitronic is the trade name for a collection of

nitrogen Nitrogen is a chemical element; it has Symbol (chemistry), symbol N and atomic number 7. Nitrogen is a Nonmetal (chemistry), nonmetal and the lightest member of pnictogen, group 15 of the periodic table, often called the Pnictogen, pnictogens. ...

-strengthened stainless steel

alloys An alloy is a mixture of chemical elements of which in most cases at least one is a metallic element, although it is also sometimes used for mixtures of elements; herein only metallic alloys are described. Metallic alloys often have properties ...

. They are austenitic

stainless steels Stainless steel, also known as inox, corrosion-resistant steel (CRES), or rustless steel, is an iron-based alloy that contains chromium, making it resistant to rust and corrosion. Stainless steel's resistance to corrosion comes from its chr ...

History

Nitronic alloys were developed by

Armco Steel AK Steel Holdings Corporation was an American steelmaking company headquartered in West Chester Township, Ohio. The company, whose name was derived from the initials of Armco, its predecessor company, and Kawasaki Steel Corporation, was acqui ...

. The first of these alloys, Nitronic 40, was introduced in 1961. Since 2022, the

trademark A trademark (also written trade mark or trade-mark) is a form of intellectual property that consists of a word, phrase, symbol, design, or a combination that identifies a Good (economics and accounting), product or Service (economics), service f ...

has been owned by Cleveland-Cliffs Steel Corp., successor to AK Steel. Electralloy is the licensed producer in North America for a wide range of Nitronic products. The Nitronic name is due to the addition of nitrogen to the alloy, which enhances the strength internally rather than being nitrided on the surface, as some steel are treated. The nitrogen is homogeneous throughout the material. Nitronic materials have about twice the yield strength of 304L and 316L.

Uses

Nitronic 30 is used to lighten transportation vehicles. Buses and railcars benefit from the high strength-to-weight ratio for weight savings. Nitronic 40 is used at cryogenic temperatures. and in the aerospace industry as hydraulic tubing. Nitronic 50 is used in marine environments, including boat shafting and solid rod rigging. Nitronic 60 and a similar alloy Gall-Tough have high resistance to

galling Galling is a form of wear caused by adhesion between sliding surfaces. When a material galls, some of it is pulled with the contacting surface, especially if there is a large amount of force compressing the surfaces together. Galling is cau ...

, a form of wear caused by adhesion between sliding surfaces, and metal-to-metal wear.

Composition

Nitronic alloys have widely varying compositions, but all are predominantly

iron Iron is a chemical element; it has symbol Fe () and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, forming much of Earth's o ...

chromium Chromium is a chemical element; it has Symbol (chemistry), symbol Cr and atomic number 24. It is the first element in Group 6 element, group 6. It is a steely-grey, Luster (mineralogy), lustrous, hard, and brittle transition metal. Chromium ...

manganese Manganese is a chemical element; it has Symbol (chemistry), symbol Mn and atomic number 25. It is a hard, brittle, silvery metal, often found in minerals in combination with iron. Manganese was first isolated in the 1770s. It is a transition m ...

and

References

{{reflist, 35em Superalloys Aerospace materials Chromium alloys