Name: MARIANE GONÇALVES DE MIRANDA SALUSTRE
Publication date: 21/08/2023
Examining board:
Name |
Role |
|---|---|
| CARLOS AUGUSTO CARDOSO PASSOS | Examinador Interno |
| ESTÉFANO APARECIDO VIEIRA | Examinador Externo |
| JESUALDO LUIZ ROSSI | Examinador Externo |
| MARCELO FALCÃO DE OLIVEIRA | Examinador Externo |
Summary: Metal matrix composites as Fe-TiB2 type have been widely investigated, since a great potential application has been identified, due to their physical and chemical properties, such as mass reduction and increased mechanical strength. Using a powder generated by the top-down technology of a microalloyed steel and a TiB2 ceramic powder, a composite with a mass ratio given by Steel (88%)/Ceramic (12%) was synthesized by the SPS (Spark Plasma Sintering) technique. The sintered samples were characterized by X-ray microtomography (CT), scanning electron microscopy (SEM), electron backscatter diffraction (EBSD), X-ray diffraction, and transmission electron microscopy (MET). Thermodynamic simulation was also performed in order to calculate the phase transformation considering equilibrium. The high densification obtained by SPS was observed and the density reduction in relation to the matrix exp = 7.44(3) g/cm³. Results associated with microabrasion indicated that the presence of TiB2 promoted an increase in wear resistance of the composite in comparison to the steel. Detailed EBSD analysis revealed that the composite matrix consists of a submicrometric substructure, and combined with TEM analyses, it was possible to propose a model of the SPS sintering mechanism at the metal/ceramic interfaces.
Keywords: SPS; Fe-TiB2; Interface; Nanostructures; Powder Metallurgy.
