Dresden 2006 – wissenschaftliches Programm
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MM: Metall- und Materialphysik
MM 4: Phase transitions I
MM 4.4: Vortrag
Montag, 27. März 2006, 11:00–11:15, IFW D
Time dependent phenomena in the athermal martensite Ni63Al37 — •Benno Ludwig, Leonard Müller, and Uwe Klemradt — II. Physikalisches Institut, RWTH Aachen University
The unexpected finding of time-dependent behaviour in athermal martensitic transformations above the MS temperature [1] has prompted further experimental studies of so called incubation time (waiting time). Several theoretical models have been put forward, which, however, disagree with each other on the detailed transformation mechanism [1,2].
In order to contribute to the ongoing discussion measurements employing different in-situ methods combined with a excellent temperature stability of ±4 mK over several days were conducted. Results clearly show the existence of incubation times between 50 s up to 112000 s despite the fact that the MS temperature is not a constant but rather a fluctuating variable on a superimposed trend. In addition the obtained data suggests a strong dependence on the thermal history of the sample. The results will be discussed in view of the competing theoretical notions.
[1] Mat. Sci. Eng. A273-275 21-39 (1999) and ref. within
[2] Scripta Mat. 50 181-186 (2004), Scripta Mat. 45 145-152 (2001)