Banca de DEFESA: MANOEL CANDIDO JUNIOR

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : MANOEL CANDIDO JUNIOR
DATE: 16/08/2023
TIME: 09:00
LOCAL: INTM PPGEA
TITLE:

MICROSTRUCTURAL CHARACTERIZATION OF TI-Ni LASER WELDERED JOINT TO OBTAIN AEROSPACE MINI SENSORS

KEY WORDS:

Martensitic Transformations, Laser Welding, Ti-Ni Alloys, Shape Memory Effect, Mechanical Properties, Martensitic Transformations, Sensors.

PAGES: 79
BIG AREA: Engenharias
AREA: Engenharia Aeroespacial
SUMMARY:

This study aims to investigate the possibility of developing a mini sensor from material extracted from a laser-welded joint made with a Ti-Ni alloy. In this way, the material could be reused, as it has a high production cost. By using materials characterization techniques, the objective is to understand the effects of welding on phase transformation, aiming for improvements in welding processes in Ti-Ni alloys, such as those used in the aerospace industry. Samples were analyzed in three conditions: heat-treated at 400 °C, 500 °C, and in the original condition. Techniques such as Optical Microscopy (OM), Differential Scanning Calorimetry (DSC), Electron Dispersion Spectroscopy (EDS), X-Ray Diffraction (XRD), and Microhardness were used to analyze the properties of the thermoelastic transformation of martensite and the composition of the alloy elements. This study can provide important information for the improvement of welding processes in Ti-Ni alloys used in critical applications. Microscopy revealed that laser welding caused significant changes in the phase transformation behavior. The EDS test indicated a significant change in the composition in the weld bead region in all studied conditions. In the Vickers Microhardness analysis, there was a significant increase in the hardness of the Ti-Ni alloy heat-treated at 500 °C compared to the alloy treated at 400 °C. The XRD test showed the presence of precipitates in the alloys treated at 400 °C and 500 °C, with the latter having the highest amount of NiTi2, Ni3Ti, Ni2.67Ti1.33, Ni3TiO, Ni(TiO3), and NiTi. The DSC test allowed the identification of the initial and final temperatures of the transformation and the energy involved in the transition.

COMMITTEE MEMBERS:
Presidente - 2619305 - CARLOS AUGUSTO DO NASCIMENTO OLIVEIRA
Interno - 1810494 - KLEBER GONCALVES BEZERRA ALVES
Externo à Instituição - JOSE ANGELO PEIXOTO DA COSTA