Dependence of the magnetostrictive properties of cobalt ferrite on the initial powder particle size distribution

Abstract

The dependence of the magnetostrictive properties of cobalt ferrite on the size distribution of thepowder used in deriving the samples from traditional ceramic approach is presented. Sample obtained by combining the smallest and largest particle size distributions gave the highestmagnetostriction and strain sensitivity (216 ppm and 1.34 nm/A, respectively), for measurementin parallel direction but the least (66 ppm and 0.38 nm/ A respectively) in perpendicular direction. Sample derived from largest particle size distribution gave the least magnetostriction and strain sensitivity (147 ppm and 0.61 nm/A, respectively) in parallel direction but the highest (126 ppm and 0.5 nm/A, respectively) in the perpendicular direction. The dependence of the magnetostrictive properties of cobalt ferrite on the size distribution of the powder used in deriving the samples from traditional ceramic approach is presented. Sample obtained by combining the smallest and largest particle size distributions gave the highest magnetostriction and strain sensitivity (216 ppm and 1.34 nm/A, respectively), for measurement in parallel direction but the least (66 ppm and 0.38 nm/A respectively) in perpendicular direction. Sample derived from largest particle size distribution gave the least magnetostriction and strain sensitivity (147 ppm and 0.61 nm/A, respectively) in parallel direction but the highest (126 ppm and 0.5 nm/A, respectively) in the perpendicular direction. V C 2014 AIP Publishing LLC.

The Direct and the Converse Magnetoelectric Effect in Multiferroic Cobalt Ferrite–Barium Titanate Ceramic Composites

“…The latter can be defined as q l = dk/dH, where k is the magnetostriction. 23 For polycrystalline CoFe 2 O 4 the magnitude of the longitudinal magnetostriction exhibits a nonmonotonic field dependence, reaching a maximal value approximately at 0.15-0.20 T for bulk, 24 which is comparable to the peaks we observed between 0.13 and 0.18 T for the longitudinal ME effect in Fig. 7.…”

“…Figure 6 illustrates the effect of poling on the magnetoelectric effect. 23 For polycrystalline CoFe 2 O 4 the magnitude of the longitudinal magnetostriction exhibits a nonmonotonic field dependence, reaching a maximal value approximately at 0.15-0.20 T for bulk, 24 which is comparable to the peaks we observed between 0.13 and 0.18 T for the longitudinal ME effect in Fig. The depoled sample shows a random and noisy ME response with very small values of electrically induced magnetization, M ME < 0.4 A/m.…”

“…25 For polycrystalline CoFe 2 O 4 the qualitative relation between the piezomagnetic coefficients q 33 = dk 3 /dH 3 and q 31 = dk 3 /dH 1 can be deduced from experimental data. 24 26 which reflects a constant volume process typical for ferroic systems with mobile ferroelastic domain walls. Taking into account these relations between diagonal and off-diagonal material coefficients, it is easy to show that a 33 % 3 4 q 33 c 33 d 33 and a 13 % À 3 8 q 33 c 33 d 33 , which well matches our experimental observation.…”

Exchange spring like magnetic behavior in cobalt ferrite nanoparticles

“…Among these, grain/particle size and their distributions are most of the important factors governing the magnetic properties in the nanomaterials. Nlebedim et al [17] observed that the particle size distribution of CoFe 2 O 4 (Co-ferrite) is an important factor in controlling the magnetostictive properties. Malik et al [18] observed double peaks in the zero field cooled and field cooled magnetic measurements performed at low field due to bimodal particle size distribution in Ni-ferrite nanoparticles.…”

“…The physical properties of these nanoparticles can also be easily tailored by controlling its microstructure and enabling them for many applications [13][14][15]. The sizes of the nanoparticles [14,16], morphology [7,13], size distribution [17][18][19], packing density [20], intergranular exchange interaction [21][22][23], and cation distribution [24,25] are some of the factors which are responsible for the modified magnetic properties in the nanomaterials. Among these, grain/particle size and their distributions are most of the important factors governing the magnetic properties in the nanomaterials.…”