Atmospheric Plasma Sprayed Cobalt Ferrite Coatings for Magnetostrictive Sensor Applications

Cobalt ferrite powder was synthesized by chemical co-precipitation followed by a heat treatment at 1100 degC for 10 h, and was subsequently deposited onto titanium and alumina substrates using atmospheric plasma spraying technique. X-ray diffraction results indicate that the as-deposited coating consists of spinel and wustite phase. The hysteresis loop measurements show that the coating has a relatively low saturation magnetization and a coercivity of 1 270 Oe for in-plane direction. Magnetostriction of the as-deposited coating at ambient temperature is -73times10
^-
6 with an applied magnetic field of 4 530 Oe