Micro-stereolithography
Anohter RP(rapid prototyping) approach, called microstereolithography, is based on stereolithography (STL), but the scale of the processing steps is reduced in size.Whereas the layer thickness in conventional stereolithography ranges between 75 qm and 500 qm, microstereolithography (MSTL) uses layer thicknesses between10 to 20 qm typically , with even thinner layers possible.
(Mikell P.Groover ,Fundamentals of modern manufacturing second edition, page 867)
Anohter RP(rapid prototyping) approach, called microstereolithography, is based on stereolithography (STL), but the scale of the processing steps is reduced in size.Whereas the layer thickness in conventional stereolithography ranges between 75 qm and 500 qm, microstereolithography (MSTL) uses layer thicknesses between10 to 20 qm typically , with even thinner layers possible.
(Mikell P.Groover ,Fundamentals of modern manufacturing second edition, page 867)
Micro-stereolithography
Micro-stereolithography
(μSL) is a novel micro-manufacturing process which builds the truly 3D
microstructures by solidifying the liquid monomer in a layer by layer fashion.
In this work, an advanced μSL apparatus is designed and developed which
includes an Ar+ laser,
the beam delivery system, computer-controlled precision x–y–z stages and CAD
design tool, and in situ process monitoring systems. The 1.2 μm resolution of
μSL fabrication has been achieved with this apparatus. The microtubes with high
aspect ratio of 16 and real 3D microchannels and microcones are fabricated on
silicon substrate. For the first time, μSL of ceramic microgears has been
successfully demonstrated
(X. Zhang, X.N.
Jiang, C. Sun,
Micro-stereolithography
of polymeric and ceramic microstructure, The
PennsylÍania State UniÍersity, UniÍersity Park, PA 16802, USA)
Manufacturing Technique
Microfabrication
:
Microfabrication
is the collection of tchniques used to fabricate devices in micrometer range.
It commonly used in microelectronics. Microfabrication processes consist of
four basic operations :
High temperature
processes to modify the substrate.
Thin film
deposition on the substrate
Patterning of
thin films and the subsrate
Bonding and
layer transfer
Under each basic
operation there are many specific tchnologies , which are sustainable for
certain devices .
(Introduction to
Microfabrication ; Sami Franssila , pg. 5,)
Microfabrication:
An important
trend in engineering and manufacturing is the growth in the number of product
and component of whose features sizes are measured in microns. Several terms
have been applied to these miniaturized items. The term microelectromechanical
systems emphasizes the miniaturization of systems consisting of both electronic
and mechanical components. The word micromachines is sometimes used for these
systems. Microsystem technology is a more general term that refers to the
product as well as the fabrication Technologies used produce them
(Groover M.P. Fundamentals of Modern Manufacturing, page.855)
Manufacturing Technigue
Electron Beam Melting (EBM)
The EBM process was first commercialised by Arcam
in Gothenburg, Sweden, in 1997. The process uses a similar approach to
selective laser sintering but replaces a laser with an electron beam-this has
interesting implications. Firstly, the electron beam may be directed by
changing the electromagnetic field through which it passes. This eliminates the
need for scanning mirrors and can significantly increase scanning speed.
Secondly, the power developed by the electron beam is very high, allowing the
process to fully melt a wide range of metals including titanium alloy using a
very fast scanning rate. However, the process is limited to conductive
materials and surfaces, as with many other layer-based processes, often require
extensive finishing-especially for tooling applications. (Rapid Manufacturing,
N. Hopkinson, p68)
Electron Beam Melting (EBM)
Electron beam melting
is one of several industrial processes that use electron beams. EBM uses a high velocity stream of electrons
focused on the work piece surface to remove material by melting and vaporization.
An electron beam gun generates a continuous stream of electrons that is accelerated
to approximately 75% of the speed of light and focused through an
electromagnetic lens on the works surface.
(Groover M.P. Fundamentals of Modern Manufacturing, page.631)
Manufacturing Technigue
Rapid Freeze
Prototyping(RFP)
The rapid freeze
prototyping (RFP) technique is developed to produce customized 3-d structures
directly from CAD models, with intricate control of microstructure and the
overall form of the scaffold. The low operating temperatures will allow the
processing of temperature- sensitive polymers and bioactive components. The RFP
technique makes use of temperature gradients to achieve pre- determined pore
size and orientation in 3-D structure.
(Paulo Jorge Bártolo, Virtual and Rapid Manufacturing: Advanced Research in Virtual and Rapid Prototyping, page 98)
Rapid Freeze
Prototyping(RFP)
Most of the existing rapid
prototyping processes are still quiteexpensive and many of them generate
substances such as smoke, dust,hazardous chemicals, etc., which are harmful to
human health and theenvironment. Continuing innovation is essential in order to
create newrapid prototyping processes that are fast, clean, and of low-cost.Dr. Ming Leu of the University of Missouri-Rolla,
Virtual & RapidPrototyping Lab. is developing a novel,
environmentally benign rapidprototyping process that uses cheap and clean
materials and can achievegood layer binding strength, fine build resolution,
and fast build speed.They have invented such a process, called Rapid Freeze
Prototyping(RFP), that can make three-dimensional ice parts of arbitrary
geometrylayer-by-layer by freezing of water droplets
(Chua C.K. Leong K.F. Lim C.S.Rapid Protyping 2th Ed.
Singpore )
Manufacturing Technigue
Benchmarking
Benchmarking is defined as the continual search for the implementation
of practices that could provide a competitive edge.* Companies differ in the
way they implement benchmarking, but it is usually adapted as a corporate
strategy used to identify the industrial leaders, promote proven techniques
and approaches, establish meaningful goals, perform business forecasting,
and analyze the overall internal process.Benchmarking can be categorized
into three major categories:
1. Internal benchmarking
2. Competitive benchmarking
3. Generic benchmarking
Internal Benchmarking: in this type of benchmarking similar activities in
various locations, departments, and units are evaluated to gain data
accessibility.
Competitive Benchmarking: This type of benchmarking is concerned with
the identification and evaluation of direct competitors to obtain data relevant
to the product under investigation and to find comparable processes in order
to gain a competitive edge.'"
Generic Benchmarking: The objective here is to evaluate the organizations
and their functions that are considered to be the industry standard in order to
achieve procedure standardization.
Benchmarking is defined as the continual search for the implementation
of practices that could provide a competitive edge.* Companies differ in the
way they implement benchmarking, but it is usually adapted as a corporate
strategy used to identify the industrial leaders, promote proven techniques
and approaches, establish meaningful goals, perform business forecasting,
and analyze the overall internal process.Benchmarking can be categorized
into three major categories:
1. Internal benchmarking
2. Competitive benchmarking
3. Generic benchmarking
Internal Benchmarking: in this type of benchmarking similar activities in
various locations, departments, and units are evaluated to gain data
accessibility.
Competitive Benchmarking: This type of benchmarking is concerned with
the identification and evaluation of direct competitors to obtain data relevant
to the product under investigation and to find comparable processes in order
to gain a competitive edge.'"
Generic Benchmarking: The objective here is to evaluate the organizations
and their functions that are considered to be the industry standard in order to
achieve procedure standardization.
(Emad Abouel Nasr,Ali K. Kamrani, Computer-Based Design and Manufacturing An Information-Based Approach, pg.13)
Benchmarking
Benchmarking is a process of comparing and measuring an organization’s
business processes against best in class operations to inspire improvement in
the organization’s performance.
The insights gained from benchmarking provide organization with a
foundation for building operation plans to meet and surpass industry best
practices and promote an overall awareness of environmental improvement issues
(G.E.M.I. Benchmarking for contiıous environmental improvement, page:1)
Financial Term
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