Differential scanning calorimetry (DSC) is used as an alternative approach to determining the time-temperature-transformation (TTT) diagram for the martensitic delta to alpha-prime transformation in a Pu-2.0 at% Ga alloy.Previous work sugests that the TTT diagram for a similar alloy exhibits an unusual double-C curve for isothermal holds of less than 100 minutes.Here,we extend this diagram to 18 hours,and confirm the double-C curve behavior.When the sample is cooled prior to the isothermal holds,the delta to alpha-prime transformation is observed as several overlapping exothermic peaks.These peaks are very reproducible,and they are believed to be the result of different kinds of delta to alpha-prime martensitic transformation.This may be due to the presence of different nucleation sites and/or different morphologies.
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