Avaliação de confiabilidade da técnica não destrutiva ultrassônica no controle de qualidade de aços ABNT 1045 tratados termicamente

• Ano de defesa: 2020
• Autor(a) principal: Costa Junior, Jose Carlos Bizerra
• Orientador(a): Martins, Carlos Otávio Damas
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Programa de Pós-Graduação: Pós-Graduação em Ciência e Engenharia de Materiais
• Palavras-chave em Português: Engenharia; Ciência dos materiais; Ondas ultrassônicas; Aço- tratamento térmico; Propriedades mecânicas
• Palavras-chave em Inglês: Ultrasonic technique; Materials characterization; Mechanical properties
• Área do conhecimento CNPq: ENGENHARIAS::ENGENHARIA DE MATERIAIS E METALURGICA
• Link de acesso: https://ri.ufs.br/jspui/handle/riufs/14742

In engineering applications, the mechanical properties of materials are decisive parameters for assessing the quality of the components produced. These properties are evaluated according to degree of compliance with the project requirements. In the process of integrity of materials and metallic structures analysis in the industrial sector, destructive testing techniques are commonly used, which in turn demand excessive time for product analysis and tend to damage the analyzed samples. Thus, this work sought to develop and evaluate methodologies for qualitative and quantitative characterization of mechanical properties of heat treated ABNT 1045 steels, using the ultrasonic nondestructive technique. In this sense, ABNT 1045 steel samples were subjected to heat treatments of annealing, normalization, quenching and tempering, under previously studied conditions. With standardized samples, correlations between the mechanical property of hardness and ultrasonic parameters were investigated by using ultrasonic "pulse-echo" technique. With the aid of statistical tools, it was also possible to quantitatively estimate the hardness values of the samples. The results obtained showed correlations greater than 80%, basing the reliability of the ultrasonic methodology developed in the characterization of mechanical properties of ABNT 1045 steels, and demonstrating the sensitivity of the sonic beam to microstructural variations of samples submitted to different thermal processes.