Banca de DEFESA: ÉTORY MADRILLES ARRUDA

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
DISCENTE : ÉTORY MADRILLES ARRUDA
DATA : 09/12/2020
HORA: 08:00
LOCAL: Sala de Reuniões do IEM
TÍTULO:
PALAVRAS-CHAVES:

AISI H13 hardened steel; ball nose end mills; high speed milling; robust parameter design; multi-objective optimization.

PÁGINAS: 175
GRANDE ÁREA: Engenharias
ÁREA: Engenharia Mecânica
RESUMO:

The design and manufacturing of complex surfaces, such as molds and dies, represent an important aspect of the entire production chain, since many of the parts manufactured today are made by processes that require these tools. The market competition scenario requires a constant technological innovation of the companies of the sector, demanding production with greater quality and precision, with shorter delivery times and production costs. High speed milling using ball nose end mills is a classic operation for the finishing of complex surfaces of molds and dies. The present work aims at the multi-objective robust optimization of the milling process of AISI H13 hardened steel using ball nose end mills. Cutting tests were carried out following a central composite design combining process variables (feed per tooth, axial and radial cutting depths and cutting speed) and noise variables (tool overhang length, workpiece tilt angle, tool wear and cutting strategy). The characteristics of interest evaluated were the machined surface roughness, the machining force and the material removal rate. Response surface methodology, robust parameter design, mean square error, factor analysis and normal boundary intersection were applied. Thus, the effects of the control and noise variables were analyzed and discussed, as well as their interactions on the characteristics of interest. Tool wear was the variable that most influenced the machined surface roughness and the machining force. The workpiece tilt angle was the variable that most influenced the material removal rate. The values obtained for surface roughness Ra ranged from 0.208 and 3.013 μm. Machining force ranged from 3.1 and 112.0 N, and the material removal rate ranged from 23.2 and 175.7 mm3/min. The mean and variance optimization of each characteristic of interest was performed, as well as the mean square error optimization. Verified the correlation between the characteristics of interest, three orthogonal and independent factors were extracted and robust multi-objective optimization was performed. Thus, 54 Pareto-optimal solutions were obtained, contributing to the improvement of quality and productivity in molds and dies manufacturing. Confirmation runs were performed and confirmed the robustness of surface roughness Ra and machining force in relation to noise variables. Tool life tests were performed and indicated a life greater than 100 min.

MEMBROS DA BANCA:
Externo ao Programa - 2503970 - ANDERSON PAULO DE PAIVA
Externo à Instituição - CARLOS HENRIQUE LAURO - UFSJ
Interno - 2277717 - EDMILSON OTONI CORREA
Externo à Instituição - FREDERICO OZANAN NEVES - UFSJ
Presidente - 394712 - JOAO ROBERTO FERREIRA
Externo à Instituição - LINCOLN CARDOSO BRANDÃO - UFSJ