During slow cooling of an iron-carbon alloy, pearlite forms by a eutectoid reaction as austenite cools below ( the eutectoid temperature ).
42.
The form of pure iron stable between 910 �C and 1390 �C, ?-iron, forms a solid solution with carbon termed austenite.
43.
Upon being rapidly cooled, a portion of austenite ( dependent on alloy composition ) will transform to martensite, a hard, brittle crystalline structure.
44.
For a eutectoid steel ( 0.78 % C ), between 6 and 10 % of austenite, called retained austenite, will remain.
45.
For a eutectoid steel ( 0.78 % C ), between 6 and 10 % of austenite, called retained austenite, will remain.
46.
The transformation from austenite to martensite is mostly accomplished through quenching, but in general it is driven farther and farther toward completion as temperature decreases.
47.
However, it is usually only effective in high-carbon or high-alloy steels in which more than 10 % austenite is retained after quenching.
48.
However, the transformation from austenite to pearlite is a time-dependent reconstructive reaction which requires the large scale movement of the iron and carbon atoms.
49.
Some have been fictionalised, weaving together what we know about Austen's world from her books and letters, creating a rich Austenite landscape ."
50.
First is that the transformation is " reversible ", meaning that heating above the transformation temperature will revert the crystal structure to the simpler austenite phase.
