There are two primary test methods used in industry to evaluate nitinol phase transformations, bend free recovery (BFR) per ASTM F2082 and differential scanning calorimetry (DSC) per ASTM F2004. Both methods are widely used, but the correlation between the method outputs for Austenite Finish (Af) temperature is not fully characterized. This can be challenging when different methods are specified or preferred by suppliers, customers, and manufacturers. DSC is a method that measures the change in energy as a function of temperature; it is a strictly thermal method. Whereas BFR monitors the displacement of a sample as temperature increases. There is a lack of published data discussing how different wire processing inputs impact the correlation between these two outputs.

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