Influence of multiaxial isothermal forging on magnetocaloric effect and magnetostructural transition in Ni-Mn-Ga-Si alloy
Year: 2024
Type: article
Abstract: The influence of as-cast and multiaxial isothermal forged structures on the sensitivity of martensite to the magnetic field and on the magnetocaloric effect in Ni-Mn-Ga-Si alloy has been studied. In the multiaxial isothermal forged state, a “necklace” structure is observed where large grains of 100–200 µm are encompassed by a layer of fine-grained structure. In this state, the martensitic transformation occurs with a shift towards the low-temperature region of about 10 K. Characteristic points of the martensitic transformation are evaluated in a magnetic field up to 12 T, revealing a sensitivity value of 0.6 K/T for both as-cast and multiaxial isothermal forged samples. Furthermore, an inverse magnetocaloric effect is identified within the martensitic transformation region for both as-cast and multiaxial isothermal forged samples under weak magnetic fields, up to 0.2 T. This inverse effect disappears at a magnetic field of 1.8 T, leaving only the direct magnetocaloric effect observable. These findings shed light on the intriguing interplay between microstructure, magnetic sensitivity, and magnetocaloric behavior in this Ni-Mn-Ga-Si alloy, offering valuable insights for potential applications in magnetic cooling technologies.
Institutions: Institute of Metal Superplasticity Problems, Institute of Physics. HI Amirkhanova, Radboud University Nijmegen, Centre National de la Recherche Scientifique, Institut National des Sciences Appliquées de Toulouse, Laboratoire National des Champs Magnétiques Intenses, Włodzimierz Trzebiatowski Institute of Low Temperature and Structure Research
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $3,120
Award: G6990451180
OpenAlex ID: W4392246748