Open Access
Effect of high-energy ball-milling on the magnetostructural properties of a Ni45Co5Mn35Sn15 alloy
(Elsevier, 2021) López García, José Luis; Sánchez-Alarcos Gómez, Vicente; Recarte Callado, Vicente; Rodríguez Velamazán, José Alberto; Unzueta, Iraultza; García, José Ángel; Plazaola, Fernando; La Roca, Paulo Matías; Pérez de Landazábal Berganzo, José Ignacio; Zientziak; Institute for Advanced Materials and Mathematics - INAMAT2; Ciencias; Gobierno de Navarra / Nafarroako Gobernua, PC017-018 AMELEC
The effect of high-energy ball-milling on the magnetostructural properties of a Ni45Co5Mn35Sn15 alloy in austenitic phase at room temperature has been analyzed by neutron and high-resolution X-ray diffraction. The ball milling promotes a mechanically-induced martensitic transformation as well as the appearance of amorphous-like non-transforming regions, following a double stage; for short milling times (below 30 min), a strong size reduction and martensite induction occur. On the opposite, for longer times, the increase of strains predominates and consequently a larger amount of non-transforming regions appears. The effect of the microstructural defects brought by milling (as dislocations) on both the enthalpy change at the martensitic transformation and the high field magnetization of the austenite has been quantitatively estimated and correlated to the internal strains. Contrary to what occurs in ternary Ni-Mn-Sn alloys, the mechanically-induced defects do not change the ferromagnetic coupling between Mn atoms, but just cause a net reduction on the magnetic moments.
Open Access
Interferometric vs wavelength selective optical fiber sensors for cryogenic temperature measurements
(SPIE, 2017) Miguel Soto, Verónica de; Leandro González, Daniel; López Aldaba, Aitor; Beato López, Juan Jesús; Pérez de Landazábal Berganzo, José Ignacio; Auguste, Jean-Louis; Jamier, Raphael; Roy, Philippe; López-Amo Sáinz, Manuel; Ingeniaritza Elektrikoa eta Elektronikoa; Fisika; Institute for Advanced Materials and Mathematics - INAMAT2; Ingeniería Eléctrica y Electrónica; Física
In this work, a preliminary study of the behavior of two different interferometric fiber optic sensors and two different wavelength selective fiber optic sensors is performed. A photonic cristal fiber Fabry-Pérot interferometer, a Sagnac interferometer, a commercial fiber Bragg grating (FBG) and a π-phase shifted fiber Bragg grating interrogated in a random distributed feedback fiber laser are analyzed. A comparison of their sensitivities and resolutions is carried out to analyze their performance as sensors for cryogenic temperatures, taking into account their advantages and drawbacks.
Open Access
Complex selective manipulations of thermomagnetic programmable matter
(Springer Nature, 2022) Irisarri Erviti, Josu; Ezcurdia Aguirre, Íñigo Fermín; Sandúa Fernández, Xabier; Galarreta Rodríguez, Itziar; Pérez de Landazábal Berganzo, José Ignacio; Marzo Pérez, Asier; Ciencias; Zientziak; Ingeniería; Ingeniaritza; Institute for Advanced Materials and Mathematics - INAMAT2; Institute of Smart Cities - ISC
Programmable matter can change its shape, stiffness or other physical properties upon command. Previous work has shown contactless optically controlled matter or magnetic actuation, but the former is limited in strength and the latter in spatial resolution. Here, we show an unprecedented level of control combining light patterns and magnetic fields. A mixture of thermoplastic and ferromagnetic powder is heated up at specific locations that become malleable and are attracted by magnetic fields. These heated areas solidify on cool down, and the process can be repeated. We show complex control of 3D slabs, 2D sheets, and 1D filaments with applications in tactile displays and object manipulation. Due to the low transition temperature and the possibility of using microwave heating, the compound can be manipulated in air, water, or inside biological tissue having the potential to revolutionize biomedical devices, robotics or display technologies.
Open Access
Giant direct and inverse magnetocaloric effect linked to the same forward martensitic transformation
(Springer Nature, 2017) Pérez de Landazábal Berganzo, José Ignacio; Recarte Callado, Vicente; Sánchez-Alarcos Gómez, Vicente; Beato López, Juan Jesús; Rodríguez Velamazán, José Alberto; Sánchez Marcos, J.; Gómez Polo, Cristina; Cesari, Eduard; Fisika; Institute for Advanced Materials and Mathematics - INAMAT2; Física
Metamagnetic shape memory alloys have aroused considerable attraction as potential magnetic refrigerants due to the large inverse magnetocaloric effect associated to the magnetic-field-induction of a reverse martensitic transformation (martensite to austenite). In some of these alloys, the austenite phase can be retained on cooling under high magnetic fields, being the retained phase metastable after field removing. Here, we report a giant direct magnetocaloric effect linked to the anomalous forward martensitic transformation (austenite to martensite) that the retained austenite undergoes on heating. Under moderate fields of 10 kOe, an estimated adiabatic temperature change of 9 K has been obtained, which is (in absolute value) almost twice that obtained in the conventional transformation under higher applied fields. The observation of a different sign on the temperature change associated to the same austenite to martensite transformation depending on whether it occurs on heating (retained) or on cooling is attributed to the predominance of the magnetic or the vibrational entropy terms, respectively.
Open Access
Fe3O4-SiO2 mesoporous core/shell nanoparticles for magnetic field-induced ibuprofen-controlled release
(American Chemical Society, 2022-12-23) García Rodríguez, Lucía; Garayo Urabayen, Eneko; López Ortega, Alberto; Galarreta Rodríguez, Itziar; Cervera Gabalda, Laura María; Cruz Quesada, Guillermo; Cornejo Ibergallartu, Alfonso; Garrido Segovia, Julián José; Gómez Polo, Cristina; Pérez de Landazábal Berganzo, José Ignacio; Ciencias; Zientziak; Institute for Advanced Materials and Mathematics - INAMAT2; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa, PJUPNA2020; Gobierno de Navarra / Nafarroako Gobernua
Hybrid magnetic nanoparticles made up of an iron oxide, Fe3O4, core and a mesoporous SiO2 shell with high magnetization and a large surface area were proposed as an efficient drug delivery platform. The core/shell structure was synthesized by two seed-mediated growth steps combining solvothermal and sol—gel approaches and using organic molecules as a porous scaffolding template. The system presents a mean particle diameter of 30(5) nm (9 nm magnetic core diameter and 10 nm silica shell thickness) with superparamagnetic behavior, saturation magnetization of 32 emu/g, and a significant AC magnetic-field-induced heating response (SAR = 63 W/gFe3O4, measured at an amplitude of 400 Oe and a frequency of 307 kHz). Using ibuprofen as a model drug, the specific surface area (231 m2/g) of the porous structure exhibits a high molecule loading capacity (10 wt %), and controlled drug release efficiency (67%) can be achieved using the external AC magnetic field for short time periods (5 min), showing faster and higher drug desorption compared to that of similar stimulus-responsive iron oxide-based nanocarriers. In addition, it is demonstrated that the magnetic field-induced drug release shows higher efficiency compared to that of the sustained release at fixed temperatures (47 and 53% for 37 and 42 °C, respectively), considering that the maximum temperature reached during the exposure to the magnetic field is well below (31 °C). Therefore, it can be hypothesized that short periods of exposure to the oscillating field induce much greater heating within the nanoparticles than in the external solution.
Open Access
Monitoring structural transformations in metamagnetic shape memory alloys by non-contact GMI technology
(IOP Publishing, 2023) Beato López, Juan Jesús; La Roca, Paulo Matías; Algueta-Miguel, Jose M.; Garayo Urabayen, Eneko; Sánchez-Alarcos Gómez, Vicente; Recarte Callado, Vicente; Gómez Polo, Cristina; Pérez de Landazábal Berganzo, José Ignacio; Ciencias; Ingeniería Eléctrica, Electrónica y de Comunicación; Institute for Advanced Materials and Mathematics - INAMAT2; Institute of Smart Cities - ISC; Zientziak; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren
Different applications based on metamagnetic shape memory alloy (MSMA) require monitoring the evolution of the martensitic transformation (MT) to optimize the actuation mechanism. To avoid interaction with the active material, a non-contact technique would be ideal. Nevertheless, non-contact detection involves complex methods like diffraction, optical analysis, or electromagnetic technology. The present work demonstrates that the MT can be monitored without interaction with the active material using a low-cost technology based on the Giant Magnetoimpedance (GMI) effect. The GMI sensor is based on a (CoFe)SiB soft magnetic wire submitted to an alternating current and whose second harmonic voltage variation allows to detect changes in the strength of the stray magnetic fields linked to the metamagnetic phase transition. The sensor has been tested using the MT of a NiMnInCo MSMA. A specific application for environmental temperature control using the non-contact GMI sensor is proposed.
Open Access
Magnetic-field-assisted photocatalysis of N-TiO2 nanoparticles
(IEEE, 2023-09-04) Cervera Gabalda, Laura María; Garayo Urabayen, Eneko; Beato López, Juan Jesús; Pérez de Landazábal Berganzo, José Ignacio; Gómez Polo, Cristina; Ciencias; Zientziak; Institute for Advanced Materials and Mathematics - INAMAT2
Nitrogen doped TiO2 nanoparticles were synthesized through solvothermal method employing Ti (IV) butoxide and HNO3 as precursors. Structural and optical characterizations confirm their nanometer nature (sizes around 10 nm) and the band-gap energy values in the UV range (3.2 eV). Nitrogen doping enhances the occurrence of optical Urbach tails extending towards the visible region. Visible photocatalytic performance (degradation of methyl orange) is correlated with maximum values in the magnetic susceptibility linked to a magnetic polarization of the anatase structure via defects (oxygen vacancies). The application of magnetic field provides a positive effect (acceleration in reaction kinetics) within the UV-Vis range.
Open Access
Long-range atomic order and entropy change at the martensitic transformation in a Ni-Mn-In-Co metamagnetic shape memory alloy
(MDPI, 2014) Sánchez-Alarcos Gómez, Vicente; Recarte Callado, Vicente; Pérez de Landazábal Berganzo, José Ignacio; Cesari, Eduard; Rodríguez Velamazán, José Alberto; Física; Fisika
The influence of the atomic order on the martensitic transformation entropy change has been studied in a Ni-Mn-In-Co metamagnetic shape memory alloy through the evolution of the transformation temperatures under high-temperature quenching and post-quench annealing thermal treatments. It is confirmed that the entropy change evolves as a consequence of the variations on the degree of L21 atomic order brought by thermal treatments, though, contrary to what occurs in ternary Ni-Mn-In, post-quench aging appears to be the most effective way to modify the transformation entropy in Ni-Mn-In-Co. It is also shown that any entropy change value between around 40 and 5 J/kgK can be achieved in a controllable way for a single alloy under the appropriate aging treatment, thus bringing out the possibility of properly tune the magnetocaloric effect.
Open Access
Martensitic transformation controlled by electromagnetic field: from experimental evidence to wireless actuator applications
(Elsevier, 2022) Garayo Urabayen, Eneko; La Roca, Paulo Matías; Gómez Polo, Cristina; Sánchez-Alarcos Gómez, Vicente; Recarte Callado, Vicente; Pérez de Landazábal Berganzo, José Ignacio; Zientziak; Institute for Advanced Materials and Mathematics - INAMAT2; Ciencias; Gobierno de Navarra / Nafarroako Gobernua
Mechanical actuators based on shape memory alloys (SMA) are becoming a key component in the development of novel soft robotic applications and surgically implantable devices. Their working principle relies in the temperature induced martensitic transformation (MT), which is responsible of the actuation mechanism. In this work, we found experimental evidence to show that the martensitic transformation can be controlled by electromagnetic field (EF) by a wireless process in ferromagnetic shape memory alloys. It is shown that the martensitic transformation can be driven by an external EF (frequency 45 kHz) while the specific absorption rate (SAR), which was determined through real-time dynamic magnetization measurements, allows the instantaneous monitoring of the transformation evolution. On the basis of the obtained results, we propose a strategy to achieve a battery-free wireless SMA actuator that can be remotely controlled. This concept can be applicable to other SMA material that exhibit a similar magneto-structural phase transition
Open Access
Influence of defects on the irreversible phase transition in the Fe-Pd doped with Co and Mn
(Rede Latino-Americana de Materiais, 2018) Bonifacich, Federico Guillermo; Lambri, Osvaldo Agustín; Pérez de Landazábal Berganzo, José Ignacio; Recarte Callado, Vicente; Sánchez-Alarcos Gómez, Vicente; Fisika; Institute for Advanced Materials and Mathematics - INAMAT2; Física; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
The appearance of BCT martensite in Fe-Pd-based ferromagnetic shape memory alloys, which develops at lower temperatures than the thermoelastic martensitic transition, deteriorates the shape memory properties. In a previous work performed in Fe70Pd30, it was shown that a reduction in defects density reduces the non thermoelastic FCT-BCT transformation temperature. In the present work, the influence of quenched-in-defects upon the intensity and temperature of the thermoelastic martensitic (FCC-FCT) and the non thermoelastic (FCT-BCT) transitions in Fe-Pd doped with Co and Mn is studied. Differential scanning calorimetric and mechanical spectroscopy studies demonstrate that a reduction in the dislocation density the stability range of the FCC-FCT reversible transformation in Fe67Pd30Co3 and Fe66.8Pd30.7Mn2.5 ferromagnetic shape memory alloys.