Banca de QUALIFICAÇÃO: LUCAS PIRES DE PAIVA BARRETO

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
STUDENT : LUCAS PIRES DE PAIVA BARRETO
DATE: 08/05/2026
TIME: 16:40
LOCAL: VIRTUAL
TITLE:

Comparative study of obtaining and characterization of polycrystalline diamond sintered via HPHT with different binders (Nb and Ta)

KEY WORDS:

Polycrystalline diamond, High Pressures and High Temperatures, Niobium, Tantalum.

PAGES: 30
BIG AREA: Engenharias
AREA: Engenharia Química
SUBÁREA: Processos Industriais de Engenharia Química
SPECIALTY: Processos Inorgânicos
SUMMARY:

Polycrystalline diamond (PCD) is widely used in cutting and drilling tools, but faces challenges such as graphitization and environmental and health concerns related to its traditional binders, such as cobalt. This study explores the route to obtaining PCD composites using niobium and tantalum as alternative binders, evaluating composites with 15 wt% binder sintered via HPHT at 1650 °C, 1750 °C, and 1850 °C under 7.7 GPa. The starting powders and milled mixtures were characterized by XRD, particle size analysis, and SEM, while the sintered samples were subjected to densitometry and Brazilian disk compression tests. The samples containing tantalum showed higher densifications and compressive strength than those containing niobium, and these properties increased at higher temperatures. Low levels of graphitization were detected, but with negligible impacts on the properties analyzed, indicating these compositions through the HPHT route as promising and more sustainable alternatives to conventional PCD.

COMMITTEE MEMBERS:
Presidente - 349801 - CARLSON PEREIRA DE SOUZA
Externo ao Programa - 2414250 - MEYSAM MASHHADIKARIMI - UFRNExterno ao Programa - 345842 - UILAME UMBELINO GOMES - UFRNExterno à Instituição - DIÊGO PIRES GURGEL - UFERSA
Externo à Instituição - MARCELLO FILGUEIRA