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Research Projects |
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1. Development of micro forming processes |
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Coordinator: G. F. Batalha
Coworkers: R. L L. P. Cerveira & F. R. D. Silva
The optimization of micro forming processes passes currently by a phase of great interest about
their tribologic parameters, being the surface topography a characteristic that shows a great
potential for imporvements on the process as a whole. This research aims at a method of
three-dimensional characterization and is concentrated in the determination of the friction behavior
and scale effect modelling.
Key-words: RCA, forming, shaping, machining
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2. Development of metallic sheet and tube hydroforming processes |
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Coordinator: G. F. Batalha & S. Degallaix
Ph.D student: G. Damoulis & J. Abrantes (USP) D. Lepicard (EC-Lille) M.Sc. student: S. Ponce
Undergraduate: C. E. Lima & B. Miranda
Project: CAPES-COFECUB EPUSP/EC-Lille.
New models for the hydroforming plasticity and failure modes are searched. In this direction
this work searchs to identify to effect parameters into the hidroforming process mechanics and
its integration into a suitable physical model to describe the hydroformed part mechanical
properties, both statics and fatigue ones. A recent study aimed the copper as well as aluminum
pipes hydroforming processes. It was developed experimental models and theoreticals study the
influence of the process.
Key-words: hidroforming, pipes. |
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3. Manufacturing Processes - Economical Process planning |
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Coordinators: G F. Batalha & M. Stipkovic
PhD students: C. Monezi, C. C. Almeida
MSc students: C. T. Matayoshi, K. Arantes & F. Kronekurt
The determination of the machining conditions can be optimized by the use of computer aided
process planning systems. Machining processes are based on a great number of variable, that
demand practical experience and qualification in order to model their influences. This study
resulted in a manufacture was optimized reduction of the cutting time and adequacy of the tool
geometry, feed rate and cutting depth, all factors in coherency with the machine tool condition.
The improvemtnt of the material flow at the manufacture of trailor welded blank was studied
under basis of of the aging propertier of the steel sheets that cannot be combined comming
from differents manufacture routes as well as and different times of stock comming from several
suppliers centers, as the laser welding and the stamping processes are influenced by aging
phenomena.
Key-word: simulation, body-in-white, TWB |
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4. Manufacture process: Moulds, Dies &Tools |
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Coordinators: G. F. Batalha & M. Stipkovic
Ph.D students: G Damoulis & J. P. Abrantes M.Sc. students: C. E. Suzuki & the Albano
Under graduate student: C. E. C. Lima, D. R. Barreto Silva, M. B. Falcão, E F. Waib, G. D. Krahenbuhl. & P. Nonaka.
Project: PACE - Partners
The design of metal forming dies of automotive parts is studied using CAD software
( Unigraphics NX3) and FEM modelling comercial codes (PAM-STAMP & LS-DYNA) aimming the
development of integrated parametric conception project of automotives body in white and
aeronautical components. Strain rate effects are studied and its consequences in phenomena such
as spring back, superplasticity, creep age forming. As well as processes such as hydroforming.
Key-words: modeling, forming, FEM, CAD. |
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5. Development of machining processes |
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Coordinator: G. Batalha, M. Stipkovic, J. Aguiar
Ph.D students: C. F. Cisneros, E.C. Bordinassi, S. Delijaicov, C. Almeida F, I. Faccio (in memorian)
M.Sc. students: G. Gallopi, G. Rossi & L. Lopes
Undergraduation students: C. E. Lima, V. Unterberger & D. R. B. Silva (PIBIC CNPq).
The forces and temperatures fields at chip-tool interface were modelled under condition of
orthogonal cutting, under great plastic strains and sticking/sliding friction on the chip-tool
interface. A FEM analysis aimmed a computational coupled model linking mechanical and thermal
stresses, taking into account corrections for the geometric non linearity on the material
behavior and strain rates, beyond a ductile fracture criterion for the determination of a
geometry for not continuous chips. Another topic of research is the monitoring and surveillance
of the wear and breakage end milling tools by acoustic emission and cutting forces as well as
milling torque using acoustics sensors. Another recent research topic of this group was the
hardmetals (WC-Co) cemented carbides surface preparation aimming the deposition of "diamond
like" carbon films. In 2002 a M.Sc. dissertation presented the development of a dynamometer
for a drilling process, which allowed for the studies on drilling processes on different steel
specimens as wells as fibre glass reinforced polymeric composites. In 2003 another MSc
dissertation concluded a study about superficial finishing effects on the high speed machined
(HSM) surface of cast irons component stamping tools. At 2004 a Ph.D thesis studied the
residual stresses and cutting forces on the hard turning process of a steel ABNT 52100
(DIN 100CrMn6) and has developped and a piezoelectric dynamometer to study the cutting forces
during the process. In 2005 it was concluded a MSc dissertation involving the hard turning
of ABNT 52100 (DIN100Cr6) steels and how the surface quality of the machined part and the tool
wear were influenced by the presence of hard coatings, e.g.: titanium nitride (TiN and TiAlN)
coatings on Cubic Boron Nitride (CBN) cutting tools. In 2006 they had occurred the defense of a
Ph.D thesis involving study of the superficial stainless steel integrity super duplex.
Key-words: machining, milling, dinamometry. |
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6. Developments for joining & assembling manufacturing processes |
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Coordinator: G. F. Batalha
M.Sc.student: Ribolla, M. Barros, D. C. Ruiz, H. Kawamura, L. Sanches and D. Stocco
Undergraduate students: M. B. Falcão, D. R. B. Silva & L. W. Feng
Project: CNPq - Instituto Fábrica do Milênio - PMR-EPUSP/UFU/UFSC/UnB.
The research aim is the Nd:YAG LASER welding process and its application in wide scale in the
automotive manufacture and assembly lines. Case studies of the welding and brazing for the
roof and side panels with and without addition material are studied, as well as the welding of
more complex geometries without addition material, using two automatized stations of welding
for two different models of vehicles body in white. It describes a case study for the use
of Nd:YAG LASER in flexible manufacture cells for the assembly of automotive body in white
in the brazilian plant of a world class automobile industry, arguing its operational duty
cycle, and the certification of assembled body in white on its correct geometry. Another work
validated the eletric resistance spot welding parameters. The samples had been tested at
shear traction tests and measured the spot weld button diameters. A failure mode was postulated,
and it allows the calculation of the minimum diameter of the spot weld point, indicating in a
reliable way the occurrence of imperfection in the area around and next to the weld button for
the case to the application of shear loads, the minimum spot weld diameter was computed as
function of the parent metal properties and had been compared with the theoretical and
experimenta lmeasurements. The strength and the failure mode of a weld spot were characterized
as function of the sheet thickness, parent metal and weld metal strength, diameter of the point
and the way of application of the load on the spot weld. The base was the model of Van den
Bossche, developed originally for plane low carbon steels and high strenght low alloy steels.
This work is bringing up to date it for new steel of the automotiva industry, as steel
BH (bake hardening) with galvanneal zinc coatings.
Key words: spot weld, eletric resistance, laser.
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