alpha iron

Definition

Noun:
- A magnetic allotrope of iron; stable below 906 degrees centigrade: Alpha iron is a specific crystalline form of pure iron that exists at relatively low temperatures. It is characterized by its magnetic properties and a body-centered cubic atomic structure.

Usage

The term "alpha iron" is a technical term used primarily in metallurgy, materials science, and engineering.
It is used to specify the phase of iron that is stable at room temperature and up to 906°C (1673°F).
It is often discussed in contrast to other iron allotropes like gamma iron (austenite) or delta iron.

Examples

Noun:
- The core of an electrical transformer is often made from silicon steel, which has an alpha iron structure.
- When steel is cooled slowly from a high temperature, it transforms into a mixture of alpha iron and cementite.

Advanced Usage

"Ferrite": In metallurgy, "alpha iron" is essentially synonymous with the term "ferrite," which is a solid solution of carbon in body-centered cubic iron.
- The microstructure of low-carbon steel consists primarily of ferrite, or alpha iron.

Variants and Related Words

Ferrite (n): A common term for alpha iron, especially when it contains a small amount of carbon in solid solution.
Gamma iron (n): The non-magnetic allotrope of iron stable between 906°C and 1401°C, with a face-centered cubic structure.
Delta iron (n): The high-temperature allotrope of iron stable between 1401°C and 1538°C, with a body-centered cubic structure.
Allotrope (n): One of two or more different physical forms in which an element can exist (e.g., graphite and diamond are allotropes of carbon).

Synonyms

Related Phrases/Concepts

Alpha phase: The phase region in an iron-carbon phase diagram where alpha iron is the stable structure.
Curie point: The temperature (770°C for iron) above which alpha iron loses its ferromagnetism, though it remains the same crystalline phase until 906°C.
Body-centered cubic (BCC): The crystal structure possessed by alpha iron.

Noun