Microwave sintering study of strontium-doped lanthanum manganite in a single-mode microwave with electric and magnetic field at 2.45 GHz
Sheila Moratal, Rut Benavente, M.D. Salvador, Felipe L. Peñaranda‐Foix, Rodrigo Moreno, Amparo Borrell
Abstract
The objective of this work is to study the changes in the physical and mechanical properties of strontium-doped lanthanum manganite (LSM) material and LSM-YSZ (ZrO2 doped with 8 mol% yttria) composite, obtained by colloidal processing and sintered by 2.45 GHz microwave sintering at 1200 and 1300 °C using two different single-mode cavities. One circular cavity with TE111 mode that has maximum in the electric field (E-field) and one rectangular cavity with TE102 mode that has maximum in the magnetic field (H-field). As compared to conventional sintering at 1300 and 1400 °C, the microwave-heated samples exhibited a denser structure for shorter sintering times. LSM-based materials showed higher heating behavior in H-field, which translates into higher energy absorption. This fact can be attributed to an electromagnetic pressure induced by the combined effect of current loops subjected to H-field. Therefore, the interaction between the material and the electromagnetic waves depends on the dominant field of them.