Effect of the voltage pulse frequency on the structure of TiO 2 coatings grown by plasma electrolytic oxidation

MOYA-BETANCOURT, S N

Journal of Physics: Conference Series

Journal of Physics: Conference Series

Año: 2022

1742-6588

lasma Electrolytic Oxidation (PEO) is used to synthetize titanium dioxide (TiO2) ceramic coatings with the appropriate selection of an electrolyte. The dimension of the microcavities and the particle size at the surface can be controlled through the pulse frequency of the voltage that is applied between the electrodes. The change of surface morphology can increase the surface area-to-volume ratio. In this work, PEO of an ASME SB-265 titanium substrate (20×20×1mm) was made in a water solution containing 8g/L Na3PO4 and 0.4g/L NaOH. Hence, the coatings were fabricated using voltage pulses of 340V for 10 minutes with a 10% duty cycle and frequencies of 1000, 1500 and 2000Hz. According to the X-ray diffractograms of the obtained samples, the sintering process at 500°C during 1 hour generated Anatase titanium dioxide porous coatings. The grain size decreased approximately from 29nm for 1000 and 1500Hz pulse frequencies until 21nm for 2000Hz. On the other hand, from the micrographs of scann