continuous cooling transformation
A continuous cooling transformation (CCT) phase diagram is often used when heat treating steel.{{Citation | title = Transformation diagrams (CCT & TTT) | url = http://www.matter.org.uk/steelmatter/metallurgy/7_1_2.html | accessdate = 2008-04-17 | archive-url = https://web.archive.org/web/20080418093559/http://www.matter.org.uk/steelmatter/metallurgy/7_1_2.html | archive-date = 2008-04-18 | url-status = dead }}. These diagrams are used to represent which types of phase changes will occur in a material as it is cooled at different rates. These diagrams are often more useful than time-temperature-transformation diagrams because it is more convenient to cool materials at a certain rate (temperature-variable cooling), than to cool quickly and hold at a certain temperature (isothermal cooling).
Types of continuous cooling diagrams
There are two types of continuous cooling diagrams drawn for practical purposes.
- Type 1: This is the plot beginning with the transformation start point, cooling with a specific transformation fraction and ending with a transformation finish temperature for all products against transformation time for each cooling curve.
- Type 2: This is the plot beginning with the transformation start point, cooling with specific transformation fraction and ending with a transformation finish temperature for all products against cooling rate or bar diameter of the specimen for each type of cooling medium..
File:TTT diagram-20201211-constant cooling rate transformations in steels.svg
See also
{{commons category|Continuous cooling transformation diagrams}}
References
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