Synthesis of Size-Controlled SrFe12O19 Using Modified Spray Pyrolysis–Calcination Method and Their Magnetic Properties

• Published in: Journal of electronic materials Vol. 43; no. 9; pp. 3574 - 3581
• Main Authors: An, Guk-Hwan, Hwang, Tae-Yeon, Choa, Yong-Ho, Shin, Kyoosik
• Format: Journal Article
• Language: English
• Published: Boston Springer US 01.09.2014; Springer
• Subjects: Applied sciences; Characterization and Evaluation of Materials; Chemistry and Materials Science; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Cross-disciplinary physics: materials science; rheology; Electronics and Microelectronics; Exact sciences and technology; Instrumentation; Magnetic properties and materials; Materials Science; Metals. Metallurgy; Methods of crystal growth; physics of crystal growth; Methods of deposition of films and coatings; film growth and epitaxy; Optical and Electronic Materials; Permanent magnets; Physics; Production techniques; Solid State Physics; Spray coating techniques; Studies of specific magnetic materials; Surface treatment; Theory and models of crystal growth; physics of crystal growth, crystal morphology and orientation; magnetic alignment; particle size control; spray pyrolysis; Hexaferrite; salt assisted; high coercivity; External field; High performance; Particle size; Spray pyrolysis; Temperature effect; Nanostructure; Ultrasonic spray pyrolysis; Spray coating; Calcining; Magnetic field effect; Particle size distribution; Coercive force; Growth mechanism; Permanent magnet; Size control; Saturation magnetization; Magnetic properties
• ISSN: 0361-5235; 1543-186X
• DOI: 10.1007/s11664-014-3228-9

Strontium hexaferrite (SrFe 12 O 19 , SrM) suitable for high-performance permanent magnet applications was synthesized by salt-assisted ultrasonic spray pyrolysis (SA-USP) and subsequent calcination. To control the particle size, the intermediate phase of SrM was collected by SA-USP and various sizes of SrM were obtained by calcining the as-prepared sample at temperatures ranging from 800°C to 1050°C. The synthesized SrM was magnetically aligned by using an external magnetic field to improve remanence. The synthesized particles were of nano- to submicron scale and nonagglomerated. The magnetic properties and squareness of the material depended on the particle size and distribution. Additionally, the NaCl added during synthesis facilitated the formation of nonagglomerated particles, while enhancing and controlling particle growth. The optimum magnetic properties were achieved at calcination temperature of 1000°C, resulting in coercivity of 5646 Oe, saturation magnetization of 73.3 emu/g, and remanence of 59.1 emu/g (80.6% of M s ).