Internal friction and longitudinal modulus behaviour of multiferroic PbZr0.52Ti0.48O3+Ni0.93Co0.02Mn0.05Fe1.95O4−δ particulate composites

• Published in: Journal of physics. D, Applied physics Applied physics, 2007-12, Vol.40 (23), p.7565-7571
• Main Authors: Venkata Ramana, M, Sreenivasulu, G, Ramamanohar Reddy, N, Siva Kumar, K V, Murty, B S, Murthy, V R K
• Format: Article
• Language: English
• Subjects: Anelasticity, internal friction, stress relaxation, and mechanical resonances; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Dielectrics, piezoelectrics, and ferroelectrics and their properties; Exact sciences and technology; Ferroelectricity and antiferroelectricity; Magnetic properties and materials; Magnetomechanical and magnetoelectric effects, magnetostriction; Mechanical and acoustical properties of condensed matter; Phase transitions and curie point; Physics
• ISSN: 0022-3727; 1361-6463
• DOI: 10.1088/0022-3727/40/23/049

Multiferroic particulate composites with composition xNi0.93Co0.02Mn0.5Fe1.95O4-delta + (1 - x)PbZr0.52Ti0.48O3 where the molar fraction x varies as ,0.,0.,0.,0.4 and 0.5 were prepared by the conventional ceramic method. The presence of two phases was confirmed by x-ray diffraction and scanning electron microscopy. The temperature variation of the longitudinal modulus (L) and the internal friction (Q-1) of these particulate composites at 104.387 kHz was studied in the wide temperature range 30-420 deg C. The temperature variation of the longitudinal modulus (L) in each composition of these particulate composites showed two abrupt minima. One minimum coincided with the ferroelectric-paraelectric Curie transition temperature (thetaE) and the other with the ferrimagnetic-paramagnetic Curie transition (thetaM) temperature. The internal friction (Q-1) measurements also showed two sharp peaks in each composition corresponding to those temperatures where the minima were noticed in the temperature variation of the longitudinal modulus behaviour. The Curie transition temperature of pure ferrite was found to be 560 deg C. Addition of 10% of ferrite to ferroelectric in a magnetoelectric (ME) composite resulted in a 360 deg C fall in thetaM and with a further increase in ferrite content the thetaM variation was found to be very nominal. However, no significant ferroelectric Curie transition temperature shift could be noticed. This behaviour is explained in the light of structural phase transitions in these multiferroic particulate composites. These ME composites were prepared with a view to using them as ME sensors and transducers.