Defeitos intrínsecos ao processo de fabrico aditivo SLM

Novas técnicas avançadas de fabrico, amplamente conhecidas como impressão 3D, estão a surgir como alternativa aos métodos convencionais, ao oferecerem a possibilidade de formas altamente complexas para um tempo e uso mínimo de material, melhorando significativamente a personalização e a eficiência dos componentes manufaturados. Contudo a introdução de novos processos de fabrico, implica necessariamente, o surgimento de novos tipos de defeitos, que têm diferentes consequências na integridade estrutural dos componentes mecânicos. Como os processos de manufatura aditiva são bastante complexos, com bastantes parâmetros e condições de fabrico, o aparecimento defeitos podem ter as mais variadas origens e, portanto, torna-se fundamental caracterizar o fenômeno responsável pelo seu aparecimento. Assim, este trabalho tem como objetivo fazer uma caracterização dos principais defeitos de fabrico associados à manufatura aditiva, mais especificamente ao Selective Laser Melting (SLM) bem como fazer uma análise integral aos fenómenos responsáveis pela sua origem. Em conclusão é estabelecido um ponto de partida para o entendimento da interação entre parâmetros de fabrico, condições de fabrico e características do pó nos defeitos intrínsecos ao processo.

Selective Laser Melting, Defeitos intrínsecos, Parâmetros de fabrico.

João Filipe Gonçalves Alves ingressou em 2024 no programa Doutoral na Faculdade de Ciências e Tecnologia – Universidade Nova de Lisboa – Portugal. Tem focado a sua investigação na área da integridade estrutural, em especial no processo de fabrico Selective Laser Melting onde procura especializar-se, estando atualmente dedicado ao seu projeto de doutoramento com o título “A Data-Driven Machine Learning Approach to Predict the Fatigue Crack Growth of Lightweight Alloys for the Aeronautical Industry”.

Teresa Leonor Ribeiro Cardoso Martins Morgado tem um doutoramento em Engenharia Mecânica no Instituto Superior técnico de Lisboa. Atualmente ocupa a posição de professora associada no Departamento de Engenharia Mecânica, no Instituto Superior de Engenharia de Lisboa, e é investigadora na Unidade de Investigação e Desenvolvimento em Engenharia Mecânica e Industrial (UNIDEMI) -FCT NOVA. As suas áreas de interesse são a Integridade Estrutural e Processos de Fabrico.

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