Pearlite is a two-phased, lamellar (or layered) structure composed of alternating layers of ferrite (87.5 wt%) and cementite (12.5 wt%) that occurs in some steels and cast irons. During slow cooling of an iron-carbon alloy, pearlite forms by a eutectoid reaction as austenite cools below 723 °C (1,333 °F) (the eutectoid temperature).

Mar 24, 2025 · Coarse: Best suited for large potted plants, trees, and shrubs, add coarse-grade perlite to the soil for plants that are prone to root rot if overwatered. Medium: Medium-grade perlite is most often used in commercial potting soils. It's a good addition to soil used for growing houseplants and container-grown flowers and vegetables. Fine: Fine-grade perlite is included …

In metallurgy, pearlite is a layered metallic structure of two-phases, which compose of alternating layers of ferrite (87.5 wt%) and cementite (12.5 wt%) that occurs in some steels and cast irons. It is named for its resemblance to mother of pearl.

Pearlite: Pearlite is the name given to a mixture of about 87.5 percent ferrite and 12.5 percent cementite. It consists of alternate layers of ferrite and cementite in steel.

Feb 7, 2025 · Perlite is a volcanic glass that is often used in gardening due to its lightweight, porous nature that aids in healthy plant development. "It is made from a type of volcanic glass called obsidian," says Susan Brandt, co-founder of Blooming Secrets.

Pearlite is an eutectoid structural component of steel, which is arranged lamellarly. pearlite is a mixture of the two phases ferrite and cementite. It occurs at carbon contents of between 0.02 and 6.67 % during coupled crystallization in iron-carbon alloys.

Pearlite is essentially a composite microstructure consisting of cementite layers (which are hard and brittle) sandwiched between ferrite layers (which are soft and ductile).

When austenite in iron-carbon alloys is transformed isothermally below the eutectoid temperature at small undercooling, it undergoes eutectoid transformation to produce a unique micro- structure termed “pearlite”, which was discovered by Sorby in 1864.

May 8, 2024 · Pearlite is a mixture of ferrite and cementite in steel, featuring alternating layers for strength and toughness, while ferrite is a pure iron phase in steel with a body-centered cubic structure, offering good ductility but lower strength.

Jul 19, 2024 · Pearlite is a two-phased, lamellar (layered or plate-like) structure composed of alternating layers of alpha-ferrite and cementite that occurs in some steels and cast irons. Pearlite only forms under specialized conditions which must be controlled to create this alloy phase.