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Abstract(s)
O crescimento exponencial da indústria nos últimos anos impulsionou o desenvolvimento de novas técnicas de produção, assim como o aperfeiçoamento das existentes, relacionando os focos de investigação com as necessidades produtivas. Para atender às necessidades da indústria no que toca ao desenvolvimento de revestimentos, é revelada uma aposta nos processos de deposição por PVD (Deposição física em fase de vapor) e CVD (Deposição química em fase de vapor), os quais ganharam grande destaque nas últimas duas décadas, com a imposição de abolir os processos de eletrodeposição, por questões ambientais e de segurança e saúde pública. Dado o uso frequente de peças revestidas não só na indústria plástica, mas em toda a indústria metalomecânica, verificou-se a importância de estudar os processos de revestimento por Crómio, realizados por PVD - Sputtering, de forma a apostar não só na questão estética, como numa possível alternativa ao crómio hexavalente, usualmente denominado por crómio 6, e nomeadamente aplicado em processos de eletrodeposição. É neste sentido que se justifica estudar o desenvolvimento de novos revestimentos finos, caracterizando-os exaustivamente e averiguando a sua adaptabilidade para aplicações óticas no ramo automóvel. Neste trabalho, foi realizado o desenvolvimento de revestimentos finos de crómio produzidos por Sputtering em peças poliméricas. A análise inicial foi efetuada ao nível do processo de deposição, permitindo estudar a parametrização adequada aos objetivos estéticos, de adesão e de transmitância. Num segundo lote, foram estudados aspetos como a espessura e rugosidade dos revestimentos obtidos, efetuando-se uma análise de adesão através do equipamento certificado para Scratch-tests, e avaliando-se a transmitância das amostras por espectrofotometria. No lote de ensaios finais, a caracterização foi mais vasta, compreendendo todos os ensaios enumerados anteriormente, e acrescendo os testes em câmara climática e de resistência à abrasão. Os revestimentos desenvolvidos foram amplamente caracterizados, possibilitando retirar ilações sobre as mais valias dos mesmos e os pontos que devem sofrer melhorias, como a resistência a alterações climáticas.
The exponential growth of industry in the last years led to the development of new manufacturing techniques as to the improvement of existing ones, linking research focuses with the manufacturing needs. To meet industry needs within coatings development, it is revealed a bet in deposition processes by PVD (Physical Vapor Deposition) and CVD (Chemical Vapor Deposition), which have gained big significance in the last two decades with the imposition to abolish the electrodeposition processes, due to environmental and public safety and health matters. Due to the frequent use of coated parts not only in the plastics industry, but also in all metalworking industry, it was realized the importance of studying the chromium coating processes, through PVD - Sputtering, betting not only on the aesthetic aspect, but also in a possible alternative to hexavalent chromium, usually denominated by chromium 6 and namely applied in electrodeposition processes. Therefore, it is of great interest to study the development of new thin coatings, checking its adaptability to optical applications in automotive industry. In the current work, it was carried out the development of thin chromium coatings through Sputtering in polymeric parts. The initial analysis was performed over the deposition process, letting to study the appropriate parameterization for the required aesthetic, adhesion, and transmittance characteristics. In a second stage, it was studied the thickness and roughness aspects of the obtained coatings, performing an adhesin analysis through a Scratch-test equipment and evaluating the transmittance though spectrophotometry. In the final stage, it was applied a wider characterization, comprising all tests carried out previously, plus the tests in climatic chamber and of resistance to abrasion. The developed coatings were widely characterized, letting to take conclusions over its strengths and aspects that should be improved, such the resistance to climate changes.
The exponential growth of industry in the last years led to the development of new manufacturing techniques as to the improvement of existing ones, linking research focuses with the manufacturing needs. To meet industry needs within coatings development, it is revealed a bet in deposition processes by PVD (Physical Vapor Deposition) and CVD (Chemical Vapor Deposition), which have gained big significance in the last two decades with the imposition to abolish the electrodeposition processes, due to environmental and public safety and health matters. Due to the frequent use of coated parts not only in the plastics industry, but also in all metalworking industry, it was realized the importance of studying the chromium coating processes, through PVD - Sputtering, betting not only on the aesthetic aspect, but also in a possible alternative to hexavalent chromium, usually denominated by chromium 6 and namely applied in electrodeposition processes. Therefore, it is of great interest to study the development of new thin coatings, checking its adaptability to optical applications in automotive industry. In the current work, it was carried out the development of thin chromium coatings through Sputtering in polymeric parts. The initial analysis was performed over the deposition process, letting to study the appropriate parameterization for the required aesthetic, adhesion, and transmittance characteristics. In a second stage, it was studied the thickness and roughness aspects of the obtained coatings, performing an adhesin analysis through a Scratch-test equipment and evaluating the transmittance though spectrophotometry. In the final stage, it was applied a wider characterization, comprising all tests carried out previously, plus the tests in climatic chamber and of resistance to abrasion. The developed coatings were widely characterized, letting to take conclusions over its strengths and aspects that should be improved, such the resistance to climate changes.
Description
Keywords
PVD – Sputtering Revestimento de polímeros Injeção de plásticos XRD AFM SEM Scratch-tests Micro abrasão Transmitância Polimetilmetacrilato - PMMA Policarbonato - PC Crómio Produção limpa Polymer coating Injection molding Micro abrasion Transmittance Polymethylmethacrylate - PMMA, Polycarbonate - PC Chromium Cleaner Production