Development of a novel magnetostrictive material with large piezomagnetic coefficient for stress sensor applications

Magnetostrictive material derived from cobalt ferrite (CFO) with high magnetostriction and strain sensitivity for stress sensor application has high technological interest in automotive industry. In the present investigation influence of Ti substitution for Fe in CFO lattice on magnetoelastic properties has been studied. XRD spectra of Co1+xTixFe2-2xO4 (0 ≤ x ≤ 0.4) samples, synthesized by conventional ceramic method, indicated the presence of single phase cubic spinel structure except for x = 0.4 composition. Lattice parameter is observed to decrease from ∼8.378Å for x = 0 to ∼8.334Å for x = 0.4 with increasing Ti substitution into the CFO lattice. Maximum magnetostriction (λ) and strain sensitivity (dλ/dH) of ∼196 ppm and ∼ 3.56 × 10−9 A−1m, respectively, are observed for Co1.2Ti0.2Fe1.6O4 composition. A remarkable ∼345% increase in dλ/dH has been observed for x = 0.2 composition compared to undoped cobalt ferrite.