Colorimetry technique on BaTiO3 and KNbO3 ceramics to determine the phase transition

In this work, colorimetry was used in order to identify the phase transition of BaTiO3 and KNbO3 ceramic. The transition of the structure produces a change of color of the ceramic bulks because their optical properties change. The transition phase was detected with a color sensor and reflectance method on ceramic bulks. CIE L*a*b* and CIE L*u*v* color spaces were used to measure the color changes reported. Experimental results showed that the changes of color are suitable for detecting the phase transition in both perovskite structures. The phase transition in the proposed ferroelectric materials was also measured by means of the dielectric constant method and the results obtained were in agreement with the temperatures reported for phase transition changes on BaTiO3 and KNbO3. Therefore, the colorimetry technique proposed in this paper proved to be suitable for detecting structure changes as a relationship between color properties and temperature.