Thermal analysis – How to interpret the cast iron cooling curve through the use of thermal analysis

How is it possible to interpret effectively the cast iron cooling curve?

Thanks to the registration of the cast iron cooling curve and its first derivative with equipment such as TCAST, thermal analysis software for cast iron, it is possible to identify some key temperatures that allow to determine the main phases of the cast iron solidification.

Hereafter the link to the video showing such fundamental phases: cast iron solidification through the use of thermal analysis.

Why is it necessary to determine the main phases of the cast iron solidification?

Monitoring in real time the behaviour of the cast iron solidification, during the cast iron production phase, it is possible to accurately verify the quality of the cast iron produced and correct right away the related production in case the production objectives are no met before solidification of the casting.

Hereafter the main phases of cast iron solidification are described.

Nucleation: such phenomenon that identifies the first formation of the solid cast iron particle. The Liquidus temperature (TLiq ) is identified at time of the cast iron cooling curve registration and it represents the temperature at which nucleation begins.

Undercooling: such phenomenon is identified at time of cast iron cooling curve registration and it is calculated as the difference between the stable temperature (TST) and the minimum eutectic temperature (TEMin). Such phenomenon allows to determine the possible cementite formation and fragility of the metal.

Recalescence: such phenomenon is identified at time of cast iron cooling curve registration and it is calculated as the difference between the maximum eutectic temperature (TEMax) and the minimum eutectic temperature (TEMin). Such phenomenon allowsto determine possible defects formation (Micro-shrinkage and Macro-shrinkage).

Eutectic transformation: the moment of eutectic transformation equals the moment at which cast iron fully solidifies. Such transformation is represented by the solidification temperature (TSol).

Eutectoidic transformation: the moment of eutectic transformation equals the moment at which the cast iron mechanical properties are identifiable. Such transformation is is calculated as the difference betweenthe minimum eutectoidic temperature (TEDMin) and the maximum eutectoidic temperature (TEDMax).

For further information: meet the technical team for a tour of TCAST thermal analysis software main functionalities and main advantages of applying thermal analysis to the cast iron production.