Banca de QUALIFICAÇÃO: MARCOS VINICYUS DE ARAÚJO OLIVEIRA

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
DISCENTE : MARCOS VINICYUS DE ARAÚJO OLIVEIRA
DATA : 07/12/2018
HORA: 10:30
LOCAL: Sala 414 - Prédio do CTEC
TÍTULO:

Effects of the tool material and lubri-cooling techniques on tool life in milling of the high-chromium white cast iron

PALAVRAS-CHAVES:

milling, high-chromium white cast iron, cemented carbide, liquid nitrogen, emulsion, three-dimensional wear parameters.

PÁGINAS: 65
GRANDE ÁREA: Engenharias
ÁREA: Engenharia Mecânica
SUBÁREA: Processos de Fabricação
ESPECIALIDADE: Processos de Fabricação, Seleção Econômica
RESUMO:

Mechanical components applied to ore crushing, drilling of oil wells and soil plowing need to be manufactured from materials with high resistance to wear, erosion and corrosion. The typical materials applied to described conditions are cold work tool steels, high-speed steels and high-chromium white cast iron (HCWCI). However, the microstructures of these materials are a challenge for machining, particularly the case HCWCI. The HCWCI presents 28 wt% of M₇C₃ carbides in a pearlite or martensitic matrix. Researches about machining of HCWCI are focused on the application of PCBN (Polycrystalline Cubic Boron Nitride) in hard turning due to high wear rates and temperatures on the cutting edges. However, in milling, conditions involve interrupted cutting and the cutting fluids can easily access the cutting region. In the latter case, the coated cemented carbides associated with lubri-cooling techniques may be an alternative to process feasibility. The aim of this work is to evaluate the effect of the coated cemented carbide grade and lubri-cooling techniques on tool lifetime in milling of the HCWIC. Therefore, two coated cemented carbide grades (PVD-TiAlN e PVD-TiAlN₂) and two lubri-cooling techniques (flood emulsion and liquid nitrogen - LN₂) were applied to the milling tests. Flank wear VB1 = 0.3 mm was the tool life criterion, which was measured by optical microscopy along the tool life and by scanning electron microscopy at the end of tool life. Three-dimensional wear parameters also were used aiming to understand the removed material from the cutting edges. The main results showed the feasibility of the coated cemented carbide application as tool material in milling of the HCWIC and LN₂ promoted an increased in tool life from two to three times, when compared to flood emulsion, depending on grade used. This result may be attributed to greater heat transfer rate in the cutting region when LN₂ is used.

MEMBROS DA BANCA:
Presidente - 1792669 - ADILSON JOSÉ DE OLIVEIRA
Interno - 1545410 - ANDERSON CLAYTON ALVES DE MELO
Externo ao Programa - 1792681 - ULISSES BORGES SOUTO