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This paper presents a novel technology that applies the
micro assembly
by (MSJ)
integrating
principlePin-plate
of Molten-Separation
Joint
from the
micro-EDM
andprecise
Nd-YAG
laser
micro-part back
to perform
micro
assembly
This has been realized by using a hybrid process that
指導老師：戴子堯
integrates micro-EDM
and Nd-YAG laser welding on a
學生：駱宏明
single machine to fabricate
micro parts and complete
precise micro assembly.
International Journal of Machine Tools & Manufacture 42 1455–1464
Jing-Dae Huang
Outline
Introduction
Hybrid machine
Results and discussion
Conclusions
Introduction
In those fields, a variety of techniques have been
considerably developed, by using diverse forms of
energy for fabricating micro parts, such as
photochemical machining and electrochemical [3–
8], mechanical machining [9], and electro-thermal
machining [10–16].
Based on the characteristics of workpiece and
product shape, one can choose an appropriate
micromachining method.
Introduction
Among electro-thermal methods, micro-EDM is a machining
method using a free electrical discharge between an
electrode and a workpiece to generate heat flow with high
energy density, so that contact force and chatter vibration can
be avoided during machining.
Therefore, it is suitable for fabricating metal
micro parts.
Introduction
Micro assembly is a feasible method to make 3D
micro metal parts.
However, the first challenge is how precisely to
position the micro parts assembled.
Masuzawa et al. [16]
(A Micro-EDM/Assembly System Unit for
Microparts Fabrication)
Introduction
Masuzawa et al. [16] has used a micro-EDM machine
to assemble a micro pin/plate tool workstation , then
the assembly process was completed by an ultrasonic
vibration to produce ultrasonic bonding between the
pin and the plate, each of which was made of different
materials.
Since the whole process was finished on the same
machine, high positioning precision can be gained.
However, to complete the assembly, a twist was
adopted to separate the micro pin at a necking.
This would limit the aspect ratio and bonding strength
of the product.
Hybrid machine
In the work, a novel hybrid process to
overcome the above stated problems is
introduced here.
An high aspect ratio can be easily attained.
Hybrid machine
(A): the stereography for the hybrid machine. (B): the stereography for microEDM mechanism. (C): the configuration of top view for three laser beams.
Hybrid machine
(A): the stereography for the hybrid machine. (B): the stereography for microEDM mechanism. (C): the configuration of top view for three laser beams.
Hybrid machine
(A): the stereography for the hybrid machine. (B): the stereography for microEDM mechanism. (C): the configuration of top view for three laser beams.
Hybrid machine
In the hybrid machine laser can be radiated 3 laser fiber optic beams.
Because 3-laser optic beams simultaneously radiate around the pin in
directions separated by 120
Results
the tensile test for the case of the pin 200 μm in
diameter
Results
Since the tensile strength of the pin increases
as its diameter increases, we can believe that
cases where the pin’s diameter is less than
200 μm have a sufficiently high strength at
the joint.
Results
Since the tensile strength of the pin increases
as its diameter increases, we can believe that
cases where the pin’s diameter is less than
200 μm have a sufficiently high strength at
the joint.
Conclusions
High aspect ratio is easily attained: the aspect
ratio of pin-plate part, length to diameter for
micro pin, can attain about 30:1
The assembled strength using the laser fusion
welding is stronger than other assembly
methods
Conclusions
The tensile test shows the failure position
usually falls at the certain position of the
assembled pin; that is, the joint strength is
enough, subjected to the axis direction load.
The hybrid machine combined micro-EDM
and Nd-YAG is suitably applied to the
precise micro assembly process.