CIOP   05384
CENTRO DE INVESTIGACIONES OPTICAS
Unidad Ejecutora - UE
artículos
Título:
Use of time history speckle pattern and pulsed photoacoustic techniques to detect the self-accommodating transformation in a CuAlNi shape memory alloy
Autor/es:
F.M. SÁNCHEZ-ARÉVALO; W. ALDAMA-REYNA; A.G. LARA-RODRIGUEZ; T. GARCÍA-FERNÁNDEZ; G. PULOS; M. TRIVI; M. VILLAGRAN-MUNIZ
Revista:
MATERIALS CHARACTERIZATION
Editorial:
ELSEVIER SCIENCE INC
Referencias:
Año: 2010 vol. 61 p. 518 - 524
ISSN:
1044-5803
Resumen:
Continuous and pulsed electromagnetic radiation was used to detect the selfaccommodation
mechanism on a polycrystalline Cu13.83 wt.%Al2.34 wt.%Ni shape
memory alloy. Rectangular samples of this alloy were mechanically polished to observe
the austenite and martensite phases. The samples were cooled in liquid nitrogen prior to the
experiments to obtain the martensite phase. Using a dynamic speckle technique with a
continuous wave laser we obtained the time history of the speckle pattern image and
monitored the surface changes caused by the self-accommodation mechanism during the
inverse (martensitic to austenitic) transformation. Using a photoacoustic technique based
on a pulsed laser source it was also possible to detect the self-accommodation phenomena
in a bulk sample. For comparison purposes, we used differential scanning calorimetry (DSC)
to detect the critical temperatures of transformation and use these as reference to evaluate
the performance of the optical and photoacoustical techniques. In all cases, the same range
of temperature was obtained during the inverse transformation. From these results, we
conclude that time history speckle pattern (THSP) and pulsed photoacoustic are
complementary techniques; they are non-destructive and useful to detect surface and
bulk martensitic transformation induced by a temperature change.13.83 wt.%Al2.34 wt.%Ni shape
memory alloy. Rectangular samples of this alloy were mechanically polished to observe
the austenite and martensite phases. The samples were cooled in liquid nitrogen prior to the
experiments to obtain the martensite phase. Using a dynamic speckle technique with a
continuous wave laser we obtained the time history of the speckle pattern image and
monitored the surface changes caused by the self-accommodation mechanism during the
inverse (martensitic to austenitic) transformation. Using a photoacoustic technique based
on a pulsed laser source it was also possible to detect the self-accommodation phenomena
in a bulk sample. For comparison purposes, we used differential scanning calorimetry (DSC)
to detect the critical temperatures of transformation and use these as reference to evaluate
the performance of the optical and photoacoustical techniques. In all cases, the same range
of temperature was obtained during the inverse transformation. From these results, we
conclude that time history speckle pattern (THSP) and pulsed photoacoustic are
complementary techniques; they are non-destructive and useful to detect surface and
bulk martensitic transformation induced by a temperature change.
Keywords: