Epitaxial Growth of Ni-Mn-Ga on Al<sub>2</sub>O<sub>3</sub>(<inline-formula><math display="inline"><semantics><mrow><mn mathvariant="bold">11</mn><mover accent="true"><mn mathvariant="bold">2</mn><mo stretchy="false">¯</mo></mover><mn mathvariant="bold">0</mn></mrow></semantics></math></inline-formula>) Single-Crystal Substrates by Pulsed Laser Deposition

Magnetic shape memory alloys have attracted considerable attention due to their multifunctional properties. Among these materials, Ni-Mn-Ga alloys are distinguished by their ability to achieve up to 10% strain when exposed to a magnetic field, a characteristic predominantly observed in single-crysta...

Full description

Saved in:
Bibliographic Details
Main Authors: Manuel G. Pinedo-Cuba, José M. Caicedo-Roque, Jessica Padilla-Pantoja, Justiniano Quispe-Marcatoma, Carlos V. Landauro, Víctor A. Peña-Rodríguez, José Santiso
Format: Article
Language:English
Published: MDPI AG 2025-05-01
Series:Surfaces
Subjects:
Online Access:https://www.mdpi.com/2571-9637/8/2/35
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Magnetic shape memory alloys have attracted considerable attention due to their multifunctional properties. Among these materials, Ni-Mn-Ga alloys are distinguished by their ability to achieve up to 10% strain when exposed to a magnetic field, a characteristic predominantly observed in single-crystal samples. Consequently, it is essential to develop nanomaterials with a crystal structure closely resembling that of a single crystal. In this study, an epitaxial Ni-Mn-Ga thin film was fabricated using Pulsed Laser Deposition on an Al<sub>2</sub>O<sub>3</sub> <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mo>(</mo><mn>11</mn><mover accent="true"><mn>2</mn><mo stretchy="false">¯</mo></mover><mn>0</mn><mo>)</mo></mrow></semantics></math></inline-formula> single-crystal substrate. The crystal structure was characterised through X-ray diffraction methodologies, such as symmetrical <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mn>2</mn><mi>θ</mi><mo>−</mo><mi>ω</mi></mrow></semantics></math></inline-formula> scans, pole figures, and reciprocal space maps. The results indicated that the sample was mainly in a slightly distorted cubic austenite phase, and some incipient martensite phase also appeared. A detailed microstructural analysis, performed by transmission electron microscopy, confirmed that certain regions of the sample exhibited an incipient transformation to the martensite phase. Regions closer to the substrate retained the austenite phase, suggesting that the constraint imposed by the substrate inhibits the phase transition. These results indicate that it is possible to grow high crystalline quality thin films of Ni-Mn-Ga by Pulsed Laser Deposition.
ISSN:2571-9637