| Título: | Strain rate effects on the fracture toughness of thermoplastic composite laminates subjected to compressive load |
| Autor: | João Antonio Brassanini Flores |
| Programa: | Engenharia Aeronáutica e Mecânica |
| Área de Concentração: | Projeto Aeronáutico, Estruturas e Sistemas Aeroespaciais |
| Orientador : | Maurício Vicente Donadon |
| Ano de Publicação : | 2022 |
| Curso : | Mestrado Acadêmico |
| Assuntos : | Materiais compósitos |
| t | Laminados |
| t | Resistência à fratura |
| t | Tenacidade |
| t | Deformação |
| t | Fibras de carbono |
| t | Ensaios de materiais |
| t | Varreduras |
| t | Engenharia de materiais |
| Resumo : | This work presents an experimental study on the fracture toughness behaviour of thermoplastic poly-arylene-ether-ketone (PAEK) reinforced with woven carbon fibres, subjected to different strain rates under compressive loading. The specimens were submitted to quasi-static and dynamic conditions. Quasi-static tests were carried out using a servohydraulic universal testing machine at a loading rate of 0.2 mm/min whilst the dynamic tests were performed using a Split Hopkinson Pressure Bar (SHPB) with the specimens subjected to strain rates of 450/s and 750/s. In addition to the data acquisition system, the SHPB apparatus was also equipped with a high-speed image system to monitor the fracture process. The results were evaluated using two different data reduction schemes: (I) digital image correlation (DIC) based strain field measurements and (II) strain energy release rate (SERR) evaluation through the J-integral method, where this scheme takes into account the anisotropy effects of the material. The tested samples were submitted to a fractographic analysis using a Scanning Electron Microscope (SEM) to verify the material fracture aspects at different strain rates. The results revealed a dependency of the fracture toughness on the strain rates, where a fracture toughness enhancement was observed at higher strain rates. |
| Data de Defesa : | 29/06/2022 |
| Texto na íntegra : | [Visualizar] |