Magnetostriction Increase of Polycrystalline Fe-Al-B Thin Sheets after Thermomechanical Process

Author(s)

Dias, M. B. S. ^[1] ; Fulop, G. O. ^[1] ; Baldan, C. A. ^[1] ; Bormio-Nunes, C. ^[1]

Affiliation

^[1] Univ Sao Paulo, Dept Mat Engn, Escola Engn Lorena, BR-12602810 Lorena, SP - Brazil

• Document type: Journal article
• Source: METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE; v. 48A, n. 12, p. 5951-5959, DEC 2017.
• Web of Science Citations: 1

Abstract

Magnetostrictive materials are applied in several types of sensors, actuators, and energy harvesting. In particular, for AC devices, thin materials are desired to reduce eddy current losses. It is well known that the magnetostriction of single crystals and textured materials is higher than in polycrystalline ones, however, the cost and manufacture speed are crucial to be used as parts of commercial devices. Therefore, polycrystalline samples are strong candidates for common applications. In this work, (Fe (x) Al100-x )(98.4)B-1.6 (x = 86.6, 82 and 79.4) alloys were rolled down to 0.7 mm of thickness and annealed at 1473 K (1200 A degrees C) for 2 hours aiming to reduce the thickness of the samples without deteriorating the magnetic properties. The alloys, even with higher contents of Al, were easily deformed to the thickness of 0.7 mm and this ability is attributed to the presence of the Fe2B phase. After the thermomechanical process, new isotropic recrystallized grains emerged and the longitudinal magnetostriction increased to 75.8, 16.9, and 3.2 pct, achieving 28.3, 28.4, and 28.8 ppm, respectively, for x = 86.6, 82, and 79.4. The piezomagnetic coefficient obtained of 4 nm/A is a suitable actuating sensitivity. (AU)

• FAPESP's process: 14/16872-0 - Optimization of the piezomagnetic properties of Fe-Al-B alloys for use in the force sensors
• Grantee: Mateus Botani de Souza Dias
• Support Opportunities: Scholarships in Brazil - Doctorate