Temperature-dependent quantitative 3{omega} scanning thermal microscopy: Local thermal conductivity changes in NiTi microstructures induced by martensite-austenite phase transition

Journal Article · Mon Sep 15 00:00:00 EDT 2008 · Review of Scientific Instruments

DOI:https://doi.org/10.1063/1.2982235· OSTI ID:21266433

Chirtoc, M ^[1]; Gibkes, J; Wernhardt, R; Pelzl, J; Wieck, A ^[2]

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1. Laboratoire de Thermophysique GRESPI-LTP, Universite de Reims Champagne-Ardenne, BP 1039, 51687 Reims Cedex 2 (France)
2. Institut fuer Experimentalphysik, Ruhr-Universitaet, 44801 Bochum (Germany)

We develop the theoretical description of 3{omega} signals from the resistive Wollaston thermal probe (ThP) of a scanning thermal microscope (SThM) in terms of an equivalent low-pass filter. The normalized amplitude and phase frequency spectra are completely characterized by a single parameter, the crossover frequency f{sub c}(k) depending on the sample thermal conductivity k. The application concerns polycrystalline NiTi shape memory alloy microstructured by focused Ga ion beam milling and implantation. The calibration of the ThP combined with a novel two-step normalization procedure allowed quantitative exploitation of 3{omega} signal variations as small as -1.75% in amplitude and 0.60 deg. in phase upon heating the sample from room temperature to 100 deg. C. This corresponds to k increase of 23.9% that is consistent with the expected thermal conductivity variation due to martensite-austenite structural phase transition. To our knowledge this is for the first time that SThM 3{omega} phase information is used quantitatively as well. The static, calibrated 3{omega} measurements are complementary to 3{omega} SThM images of the patterned sample surface. The local SThM measurement of temperature-dependent thermal conductivity opens the possibility to imaging structural phase transitions at submicron scale.

• OSTI ID: 21266433
• Journal Information: Review of Scientific Instruments, Vol. 79, Issue 9; Other Information: DOI: 10.1063/1.2982235; (c) 2008 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0034-6748
• Country of Publication: United States
• Language: English

Related Subjects

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
36 MATERIALS SCIENCE
AUSTENITE
GALLIUM IONS
ION BEAMS
MARTENSITE
MICROSCOPY
MICROSTRUCTURE
MILLING
NICKEL ALLOYS
PHASE TRANSFORMATIONS
SHAPE MEMORY EFFECT
TEMPERATURE DEPENDENCE
TEMPERATURE RANGE 0273-0400 K
THERMAL CONDUCTIVITY
TITANIUM ALLOYS
TRANSITION TEMPERATURE