Lim, Jiunn Hsuh
(2012)
The Effect Of Reinforced-Epoxy Coating On The Bending Modulus Of Micro-Cantilever Using Phase-Shift Shadow Moiré.
PhD thesis, Universiti Sains Malaysia.
Abstract
Applying an accurate bending modulus value of the material is important in the
design and analysis of the reinforced-epoxy coated PET cantilevers. This is because
the accurate bending modulus value is important in evaluating the effect of the
various coatings onto the micro-cantilever. This research is aimed at applying the
phase-shift shadow moiré method (PSSM) for the deflection measurement of
reinforced-epoxy coated PET micro-cantilevers in order to determine the bending
modulus of the micro-cantilever material. The PSSM was initially developed to
measure the deflection of a miniaturized copper cantilever and the feasibility of the
method was studied to measure micro-deflection. The PSSM was then modified and
improved using image processing techniques to enhance the poor visibility moiré
fringes before applying it to measure the deflection of a silicon micro-cantilever. The
silicon micro-cantilever specimen was fabricated using surface micro-machining
technique. The improved PSSM method was successfully applied to process poor
visibility fringe patterns and deflection data was extracted. A study on the effect of
different coating materials in the reinforced-epoxy coated PET micro-cantilever was
then carried out. The samples were fabricated by applying the aluminum-epoxy and
graphite-epoxy coatings on PET sheets through a mold. The micro-cantilevers
specimens were then released by cutting the PET with coating according to the
patterns of the mold. The various types of the reinforced-epoxy coatings were found
xviii
to affect the bending modulus of the coated PET micro-cantilevers. The bending
modulus increased as the percentages of the aluminum and graphite reinforcement in
the epoxy increased. The study of the effect of the coating materials were extended
by using the finite element analysis (FEA). The bending modulus values of the
various types of coating materials determined from experimental work were applied
as the input parameter and the thickness of the coatings were altered. The
investigation from the FEA suggested that the optimum thickness of reinforcedepoxy
coating is about 180 μm based on the increment of the stiffness. The research
work was focused on the specimen preparation and improvement of the PSSM
method with image enhancement technique, as well as the study of the effect of the
coating on PET cantilever. The research shows that the improved PSSM method is
capable of measuring the micro-deflection with minimum error and the bending
modulus of the micro-cantilever can be altered by using different coating materials.
Without changing the major dimensions of the micro-cantilever, the bending
modulus of the composite cantilever material can be varied and therefore microcantilevers
with different sensitivities can be produced.
Actions (login required)
|
View Item |