Magnetostrictive properties of FeAl/polyester and FeAl/silicone composites

Significance Statement

More industrial interest in control systems has led to the spread of the actuator as well as sensor fields. Therefore, magnetostrictive materials are of importance with regards to torque and force sensors by determining the change in the magnetization caused by an applied stress. Various materials have been selected for several magnetic sensors demand. However, monolithic materials suffer from eddy current losses at high frequencies. For this reason, magnetostrictive composite materials synthesized by blending magnetostrictive particles in a non-metallic matrix possess high electrical resistivity and therefore do not suffer the eddy current losses. Such materials are excellent building blocks for magnetostrictive sensors operating at high frequencies.

Fe100-x Alx ribbons obtained through melt spinning exhibit high magnetostriction for a value of x about 19. This method can be adopted to make powder cheaply and consequently produce magnetostrictive composites.

Spanish researchers Graciela Riesgo García and colleagues studied the magnetostriction in Fe81Al19 composite powder randomly distributed and oriented in silicone and polyester matrixes. They obtained nanocrystalline powder of Fe81Al19 through mechanical milling from ribbons with the same composition synthesized through rapid solidification process. This enabled them to shorten the milling time, consequently reducing oxidation of the constituent powders. Their work is published in Materials Science and Engineering B.

The authors used high purity aluminum and iron metals to prepare alloy ingots of Fe81Al19 by induction melting. They produced ribbons from these ingots via flow casting and determined their chemical composition. The ribbons were cropped before milling, which was done in a water-cooled steel vessel. A 4wt% benzene was adopted as the process control agent in the milling. This allowed the particles to downsize easily without welding on each other.

The authors analyzed the X-ray diffraction patterns of the Fe-Al alloy powder at varying milling times and determined lattice strain as well as crystalline size of the powder. They used powders milled for 100 h to synthesize two composites. In one of the composites, they used polyester matrix and silicone in the other. In the polyester composite, the researchers cured one sample without applied magnetic field and two with applied magnetic field. This was in a bid to configure the composite particles in the longitudinal and transverse directions. For the case of silicone, two samples were cured with an applied magnetic field.

The authors observed that the crystallite size was less than 7 nm after milling for 10 h, which indicated rapid nanocrystallization. After milling for 10 hours there was an increase in the crystallite size and this was attributed to grain growth as well as recrystallization. Lattice strain was observed to increase with the milling time.

Milling produced particle size reduction and cold welding. For milling time until 10 h, grinding produced material refinement with a decrease in the particle size, but when the milling time increased, cold welding was responsible for the particle size increase. It was also observed that silicone composites cured in an applied magnetic field in the longitudinal direction reached a saturation magnetostriction of 45 ppm.

Magnetostrictive properties of FeAl polyester and FeAl silicone composites - advances in engineering

About The Author

Graciela Riesgo García completed the studies of Merchant Marine at the University of Oviedo, Spain, in 2004. From 2002 to 2008 she worked as Second Officer and Chief Mate in oil and chemical tanker vessels of different shipping companies. From 2010 to 2016 she worked as associated professor in the Nautical Science and Technology Department of the University of Oviedo. She currently works as a technician in the Jovellanos Maritime Safety Centre that depends organically on the Spanish Maritime Safety Agency. In this Centre she collaborates in the “European Picasso Project” (Preventing Incidents and Accidents for safer Ships in the Oceans). Her research is focused in the study of magnetorheological materials for its application in sensors.

About The Author

Francisco Javier Carrizo Medina, born in León, Spain in 1960. Degree in Chemistry at the University of Oviedo (Spain). PhD in Physics at the University of Oviedo in 1991. Joined to the Physics Department of this University, he currently holds a position of titular professor of Applied Physics at the Polytechnic School of Engineering of Gijón. As a researcher, he has always worked in the field of magnetism: magnetic anisotropy, magnetostriction and magnetic sensors. Currently is working on the preparation and study of composite materials made of magnetic dust dispersed in polymeric matrixes.

About The Author

Laura Elbaile Viñuales was born in Huesca, Spain in 1957. She received her BSc degree in Physics from the University of Zaragoza, Spain and she obtained in 1996 her PhD in Physics at the University of Oviedo (Spain). Since 1999, she is working as Assistant Professor in the Physics Department of Universidad de Oviedo.

Her main scientific activity was focused on the study of the magnetic properties of amorphous and nanocrystalline soft magnetic materials. At present, she is interested in the study of magnetic properties of composite materials.

About The Author

Rosario Díaz Crespo was born in Oviedo, Spain in 1966. She received her BS degree in Physics in 1990 from the Cantabria University, Santander, Spain, and her PhD degree in Physics in 1998 from the University of Oviedo. Currently, she is an Assistant Professor in the Department of Physics. at the University of Oviedo, Spain. Her recent research interests include magnetic composites, magnetic sensors and micromagnetic simulations.

About The Author

Ranier Sepúlveda began his research career at the Universidad Simón Bolívar (Caracas – Venezuela) in 2000. His Bachelor thesis was based on the fabrication, microstructural and mechanical properties characterization of TiC-VC cemented carbide. After that, he joined the Biomimetic and Multifunctional Materials Group at the Universidad de Sevilla (Seville – Spain) under the Antonio Ramirez de Arellano Lopez and Julian Martinez Fernandez´s guidance to accomplish his PhD. During those years, his research was based on the development of SiC/Si composites bioinspirated materials. As a result, more than 10 papers were published, over 20 international and national congress contributions, involved in 6 international research projects, and 2 international traineeship were successfully conducted. Besides that, he was part of the creation of a technological based spin-off company named Biomorphic SRL.

Nowadays, he is a Senior Lecture at the Engineering and Material Science Department of the Universidad de Sevilla where develops an intense teaching and research activities. It was been involved in several research projects referring to the fabrication of Ti porous materials by powder metallurgical methods. Currently, Ranier Sepúlveda lead an innovative research line, supported by public and private funds, to develop new Fe-based porous materials using the freeze-casting fabrication process. The many object is to produce materials with a controlled pore morphology and certain catalytic properties. Indeed, the redox capacity of Fe-base materials turn it into a viable method to produce and purify hydrogen. This research line has numerous international and national collaborators, and have already several papers published on this matter.

About The Author

José Ángel García Díaz received his BSc degree in Physical Sciences from the Complutense University of Madrid, Spain, in 1978 and his PhD degree in Physical Science from the University of Oviedo, Spain, in 1986. At present, he is Assistant Professor of the Physics Department of the University of Oviedo.

His research interest include magnetic materials and nanostructures with the focus on biological assays and detection systems.


G. Riesgo1, J. Carrizo2, L. Elbaile2, R.D. Crespo2, R. Sepúlveda3, J.A. García2. Magnetostrictive properties of FeAl/polyester and FeAl/silicone composites. Materials Science and Engineering B, volume 215 (2017), pages 56–63.

Show Affiliations
  1. Dpto. de Ciencias y Técnicas de la Navegación, Universidad de Oviedo, Campus universitario de Gijón, 33203 Gijón, Spain
  2. Dpto. de Física de la Universidad de Oviedo, c/ Calvo Sotelo s/n, 33007 Oviedo, Spain
  3. Dpto. de Ingeniería Mecánica y de los Materiales, Universidad de Sevilla, Isla Cartuja, 41092 Sevilla, Spain


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