L2-6768 — Annual report 2015
1.
Relation between the microstructure and the electrocaloric effect of relaxor ferroelectric Pb(Mg[sub](1/3)Nb[sub](2/3))O[sub]3-PbTiO[sub]3 ceramics

In the contribution the effect of the grain size of PMN-10PT ceramics on the electrocaloric temperature change of the material is studied. We showed that a substantial enhancement of the EC effect is achieved with a properly engineered ceramic microstructure. Highly dense bulk ceramics with grain sizes in the micron range (≈ 2 µm to ≈ 10 µm) were prepared. The material with ≈ 98 % relative density and 3.6-μm grains is characterized by a high breakdown strength exceeding 160 kV cm-1, and a large EC temperature change (ΔTEC) of 3.45 °C. This value is the highest reported so far for Pb-based perovskites and is comparable to best results obtained by multi-critical-point enhancement.

B.04 Guest lecture

COBISS.SI-ID: 28619559
2.
Characterization of 0.9Pb(Mg[sub](1/3)Nb[sub](2/3))O[sub]3-0.1PbTiO[sub]3 electrocaloric elements prepared by tape casting

The aim of this work was to prepare multilayer ceramic elements by tape casting. The PMN-10PT ceramic powder was prepared by mechanochemical activation of constituent oxides. The multilayer samples were obtained by tape-casting the slurry and laminating, and they consisted of 5 layers of PMN-PT tape and internal Pt electrodes. Sintering was performed at 975 °C. The microstructures of multilayer samples were uniform with grain sizes of 1.6 μm. The room-temperature values of dielectric permittivity were similar for multilayers as well as bulk ceramics sintered of the same ceramic powder, as well as the indirectly determined electrocaloric temperature change.

B.03 Paper at an international scientific conference

COBISS.SI-ID: 28888615
3.
Electrocaloric effect in 0.9Pb(Mg[sub](1/3)Nb[sub](2/3))O[sub]3-0.1PbTiO[sub]3 bulk ceramics with grain sizes in micron range

In the contribution the relation between the grain size and the electrocaloric temperature change was discussed. The author Marko Vrabelj won the 2nd award in the section of young researchers at the 23rd international conference on materials and technologies (September 2015, Portorož, Slovenia).

E.02 International awards

COBISS.SI-ID: 28940839