Critical Temperature of Steel
Critical temperature of steel defines phase transition between two phases of steel. As the steel is heated above the critical temperature, about 1335°F (724°C), it undergoes a phase change, recrystallizing as austenite. There are two types of critical temperature:
- Lower critical temperature (Ac1). The temperature at which austenite starts to transform from ferrite.
- Upper critical temperature (Ac3). The temperature at which austenite is completely transformed from ferrite.
In the Fe-C system, there is a eutectoid point at approximately 0.8wt% C, 723°C. The phase just above the eutectoid temperature for plain carbon steels is known as austenite or gamma.
We hope, this article, Critical Temperature of Steel, helps you. If so, give us a like in the sidebar. Main purpose of this website is to help the public to learn some interesting and important information about materials and their properties.