Article

Estudo da Furação de Laminados Carbono/Epóxido com Diferentes Brocas

01/2004;
Source: OAI

ABSTRACT A furação de placas em materiais compósitos surge da necessidade de efectuar a montagem das peças em estruturas. Embora seja corrente o uso de técnicas tradicionais de furação, estas devem ser devidamente adaptadas de forma a reduzir a geração de danos mecânicos e térmicos. O defeito mais grave é a delaminação, que nem sempre é visível à superfície e pode causar o colapso prematuro das estruturas em serviço. A correcta definição das ferramentas a utilizar na execução dos furos bem como a selecção adequada das estratégias de corte que permitam evitar a ocorrência de delaminação é uma preocupação que deve ser sempre tida em conta. Para a avaliação dos danos provocados nas peças antes da sua entrada em serviço utilizam-se meios de controlo não-destrutivo, apoiados na definição de critérios de avaliação do dano. Neste artigo são analisados os resultados obtidos através do uso de diversas geometrias de broca e estratégias de furação em placas carbono/epóxido e apresentados os resultados de duas técnicas de controlo não-destrutivo, assim como o processamento e análise de imagem com técnicas no domínio da Visão Computacional. Os resultados obtidos permitem estabelecer critérios de selecção de ferramentas que minimizem a delaminação.

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