New observations on the thermal arrest memory effect in Ni-Ti alloys

Ni-Ti shape memory alloys demonstrate a unique phenomenon known as thermal arrest memory effect or TAME. In the present work, a new observation regarding the nature of this phenomenon in Ni-Ti alloys has been made. It is observed that the thermal arrest of the reverse transformation causes the endotherm of the pre-existing martensite microstructure to drift up to 9 K above the reverse transformation temperature of the alloy. The analysis suggests that this could be due to the growth of the pre-existing primary martensite plates.