Eventos Anais de eventos
COBEM 2023
27th International Congress of Mechanical Engineering
Preliminary analysis on the effects of thermal aging and corrosion on optical and morphological properties of chromium-based absorber surfaces deposited by Magnetron Sputtering
Submission Author:
Thaís Almeida , PB
Co-Authors:
Thaís Almeida, Kelly Cristiane Gomes, Francielle Cristine Gonçalves
Presenter: Thaís Almeida
doi://10.26678/ABCM.COBEM2023.COB2023-2076
Abstract
Solar energy presents itself with great potential as renewable alternative source, even if it is utilized in small scale in photothermic conversion, due to limitations in applicability of solar collectors. In this context, the solution is to apply selective surfaces in this type of equipment, to absorb as much as possible of the solar radiation and emit the least possible heat. The present work has the objective to study the effects of thermal aging and the durability under corrosive environments on chromium-based absorber surfaces. Two solar surfaces are being studied (Cr2O3 – Cr/Cr2O3 and Cr2O3 – Cr/Cr2O3 – SiO2), deposited by Magnetron Sputtering in stainless steel AISI 304 surface-treated with electropolishing. All samples are going to be characterized optically and morphologically using UV-Vis-NIR and Infrared Spectrophotometry, Atomic Force Microscopy, Optical Profilometry and X-Ray Diffraction. After the initial characterization, all samples are going to be submitted to customized aging tests (25, 200, 350 and 500 °C) to evaluate their thermal stabilities and its effects on their absorptances. All samples are going to have their chemical stabilities analyzed under corrosive environment and subsequently their optical proprieties will be characterized again. Preliminary analysis show that the presence of SiO2 doesn’t interfere on the absorptance, even if the difference between the values of band-gaps suggests otherwise. This requires further investigation of the emittance and selectivity to analyze if the SiO2 interferes or not on the applicability of the surfaces. A corrosion test was executed and the sample with SiO2 presented a better result on resistance, as the surface is almost intact after being exposed to the corrosive environment.
Keywords
selective surface, magnetron sputtering, thermal aging, corrosion, Durability
