Banca de DEFESA: ANA BIATRIZ GUEDES DO NASCIMENTO

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : ANA BIATRIZ GUEDES DO NASCIMENTO
DATE: 13/12/2026
TIME: 10:00
LOCAL: Plataforma de Google meet
TITLE:

Study and Characterization of the CuWMoTaV High-Entropy Alloy Processed by High Energy Milling and Spark Plasma Sintering

KEY WORDS:

powder metallurgy; equiatomic systems; BCC solid solution; thermal stability; refractory materials

powder metallurgy; equiatomic systems; BCC solid solution; thermal stability; refractory materials

PAGES: 122
BIG AREA: Engenharias
AREA: Engenharia de Materiais e Metalúrgica
SUMMARY:

Technological advancement in strategic sectors, such as aerospace, nuclear, and power generation, demands the development of materials capable of maintaining structural stability, mechanical strength, and chemical integrity under extreme temperature and pressure conditions. In this context, refractory high entropy alloys stand out as a new class of metallic materials, composed of multiple elements in near-equiatomic proportions, which provide high thermal stability and corrosion resistance. In this work, the CuWMoTaV alloy was produced by powder metallurgy, using the combination of high-energy milling and spark plasma sintering. The study involved different milling times (5 hours, 10 hours, 20 hours, and 30 hours) and different sintering dwell times (1 minute, 5 minutes, and 10 minutes), with the objective of evaluating the influence of these parameters on phase formation, microstructure, and the final properties of the material. X-ray diffraction indicated the formation of a solid solution with a body-centered cubic crystalline structure starting from the highest milling times, with the best result obtained at 30 hours. Analyses by scanning electron microscopy and energy dispersive spectroscopy evidenced a homogeneous chemical distribution of the elements and densification superior to 98% after sintering. The increase in milling time resulted in microstructural refinement and a reduction in crystallite size, while the extension of the sintering dwell time favored controlled grain growth and the decrease of residual porosity. The samples presented Vickers hardness between 750 and 850 HV, in addition to good thermal stability and corrosion resistance, confirming the alloy's potential for applications in severe environments. These results confirm that the combined route of high-energy milling and spark plasma sintering is effective for the production of CuWMoTaV high entropy alloys, with the 5 minute dwell time being the optimized parameter for obtaining superior mechanical properties and microstructural stability.

COMMITTEE MEMBERS:
Presidente - 2414250 - MEYSAM MASHHADIKARIMI
Interno - ***.121.804-** - UILAME UMBELINO GOMES - UFRN
Externo à Instituição - MARCELLO FILGUEIRA - UENF