A coming revolution...

1. 3d Printing
Name : Siddhant H Pathak
Roll no: 21
Sem : 2
Department of Materials Science

2. • Last winter, Jan 2013 in Michigan USA “kaiba geon-
-frido” Age-3 months was struggling between life
and death, it was born with a very deadly defect
called “tracheobronchomalacia”
• That is the Pulmonary artery(of the heart) was
intertwined over his bronchi(left wind pipe of his
lung)hence air was unable to reach his left side
of the lung and he had to be kept on ventilator
• In such a case it was impossible for little kaiba
to lead a normal life because his left wind pipe
was completely crushed by pulmonary artery
the defect was in the basic structure of his body
• No kind of repairing would be able to cure
kaiba because the defect was irrepairable
the only way out would be to replace the very
part of little kaiba’s body or he would die after all
no body having such defect have lived till date.
• At this hour of need the chief surgeon of Michigan
hospital Glenn Green called for 3d printer
and its expert Scot Holister, a biomedical engineer
at Michigan University

3. 0
• After a tedious and gruesome analysis
of size, geometry, structure and working
of the wind pipe it was decided that this
windpipe would be created artificially
by the 3d printer to exactly suit the
requirement of little kaiba by a special
type of thermoplastic called
“Polycaprolactone”
• Now Polycaprolactone is an extremely
inert and biocompatible material,
this was 3dprinted to give a form of
hollow structure like that shown

4. • This designed piece was bound
over the defected part of little
kaiba
• The baby who could not have lived more
than a few minutes out of the ICU
was given a gift of living an absolutely
normal life. All because of a desktop PC
sized gadget …….. 3-d printer

5. Index
•What is 3d printing
•Digital Printing
•3d printing processes
•Applications
•References

6. What is 3d printing ?
• 3d printing is a kind of manufacturing process
in which you can make a three dimensional
solid object of virtually any shape and type
from its digital model
• This digital model can be created by CAD(a
digital software) or by 3d scanning
by
•
3d printing is different from traditional
manufacturing process as the tradional method
used for the purpose of manufacturing is
a subtractive process, i.e procedures like
filing, cutting, grinding, milling etc are used

7. • to remove the unwanted material in order to give the desired shape for the
desired quality and working of a product
• 3d printing is an exactly opposite process termed as additive manufacturing in
which the objects are created through sequential layering i.e. the material of
which the substance is to be made is printed layer after layer in order to get the
final product.
• Hence the biggest benefit when is made on
large scale through 3d printing is that
“There is completely 0 wastage of material”
• Hence 3d printer is a type of industrial
robot that is capable of carrying out
additive manufacturing process under
computer control.

8. Digital Pr inting
• To perform a print, the machine reads the design from 3D printable file (STL file)
STL(STandard Lithiography aka Standard Tesselation Language) it is a widely
used file format supported by many software packages widely used in rapid
prototyping and CAM
• The STL format are specified in both ASCII and binary representations. However
binary files are more common, since they are more compact.
• An STL file describes the cross sectional surface of the object by the unit normal
and vertices of the triangles using a three-dimensional Cartesian coordinate
system.
• The layers cross sectional layers of the material which corresponds to the digital
design are joined or automatically fused together to obtain the final shape by
the command written in STL format

9. • The actual printing is carried out by
the mechanism of the printer
where two nozzles as shown on
the right oozes out the material
drop by drop, materials used are
normally a thermoplastic like
polystyrene, Polylactic acid,
HDPE etc i.e the materials with low
melting point and good thermal
and structural stability.
• Here the rod on which the nozzle is
bound with moves in the Z-direction while the platform on which the desired
object is being formed can move in the X-Y plane
• The movement of these planes would be synchronised such that they will
together move to exactly form the desired object.

10. • Like normal printers even 3d printers have resolution that describes the thickness
of the material and is measured in dots per inch(dpi) or mirometers
• Typical layer thickness is around 100 μm (250 DPI), although some machines such
as the Objet Connex series and 3D Systems can print layers as thin as 16 μm
(1,600 DPI) with their X-Y resolution comparable to that of laser printers where
the particles (3D dots) are around 50 to 100 μm (510 to 250 DPI) in diameter.
• Construction of a model with contemporary methods can take anywhere from
several hours to several days, while this additive system can typically reduce this
time to a few hours
• Traditional techniques like injection molding can be less expensive for
manufacturing polymer products in high quantities, but additive manufacturing
can be faster, more flexible and also less expensive especially when producing
relatively small quantities of parts not mentioning that you also have a size
advantage over traditional machinery as 3d printer is almost the size of a desktop
computer.

11. 3d printing processes
• A large number of additive processes are available. They differ in the way layers
are deposited to create parts and in the materials that can be used.
• Some methods melt or soften material to produce the layers, e.g. selective laser
melting (SLM) or direct metal laser sintering (DMLS) for which Titanium alloys,
Cobalt Chrome alloys, Stainless Steel and Aluminiums are used.
• Selective laser sintering (SLS), which uses thermoplastics ceramic powder and
metal powder, Fused deposition modeling (FDM) which uses thermoplastics
eutectic metals, rubber metal clay, plasticine and even edible materials
• Some methods cure liquid materials using different sophisticated technologies,
e.g. stereolithography (SLA). Which includes laminated object manufacturing
(LOM) in which thin layers are cut to shape and joined together (e.g. paper,
polymer film, metalcoils).
• Each method has its own advantages and drawbacks

12. Fused Deposition Modeling
• In fused deposition modeling the model or part is
produced by extruding small beads of material
which harden immediately to form layers.
• A thermoplastic filament or metal wire that is
wound on a coil is unreeled to supply material to
an extrusion nozzle head. The nozzle head heats
the material and turns the flow on and off.
• Typically stepper motors or servo motors are
employed to move the extrusion head and adjust
the flow and the head can be moved in both
horizontal and vertical directions.
• Various polymers are used, including acrylonitrile butadiene styrene (ABS),
polycarbonate (PC), polylactic acid (PLA), high density polyethylene (HDPE) and
polyphenylsulfone (PPSU). In general the polymer is in the form of a filament,
fabricated from virgin resins.

13. Granular Mat er ials Binding
• Another 3D printing approach is the selective
fusing of materials in a granular bed. The technique
fuses parts of the layer, and then moves the
working area downwards, adding another layer of
granules and repeating the process until the
piece has built up.
• This process uses the unfused media to support
overhangs and thin walls in the part being
produced, which reduces the need for temporary
auxiliary supports for the piece. A laser is typically
used to sinter the media into a solid. Examples
include selective laser sintering (SLS) which uses
both metals and polymers and direct metal laser
sintering (DMLS) which uses only metals.
• Selective Laser Melting (SLM) does not use sintering for the fusion of powder granules but
completely melts the powder using a high-energy laser to create fully dense materials in a
layerwise method with similar mechanical properties to conventional manufactured metals.

14. Laminated object manufacturing
• In some printers, paper can be used as the
build material, resulting in a lower cost to print.
During the 1990s some companies marketed
printers that cut cross sections out of special
adhesive coated paper using a carbon dioxide
laser, and then laminated them together.
• In 2005, Mcor Technologies Ltd developed a
different process using ordinary sheets of office
paper, a Tungsten carbide blade to cut the
shape, and selective deposition of adhesive and
pressure to bond the prototype.
• There are also a number of companies selling
printers that print laminated objects using thin
plastic and metal sheets.

15. Photo Polymerisation
• In photopolymerisation, a vat of liquid
polymer is exposed to light from a DLP
projector under safelight conditions. The
exposed liquid polymer hardens.
• The build plate then moves down in small
increments and the liquid polymer is
again exposed to light. The process
repeats until the model has been built. The
liquid polymer is then drained from the
vat, leaving the solid model.
• In some inkjet type system like object
polyjet Photopolymer material is sprayed
in ultrathin layers(16-30 microns), each
layer is cured with UV light which
produces fully cured objects that can be handled and used immediately.

16. Applications
• Fire Arms
Cody Wilson in the picture below, is a student at texas, America he has made a
semi-Automatic rifle at
home
3d printed …of course !!!
• US department of
homeland security has
disclosed of plans to
design a working plastic
gun that could be
downloaded and
reproduced by anybody
with a 3D printer.

17. This printer is a brainchild of Dr.
Behrokh Khoshnevis from the
University of Southern California.
Here we can see two tracks
guiding the Contour Crafting
device along as it extrudes
cement along a programmed
floor plan.
It is hoped that the device will be
used to provide low-cost shelter
for the estimated 1 billion people
living in substandard housing
around the globe. It could also be
used to quickly restore housing to
those lost in natural disasters,
such as those displaced by the
hurricane in the Philippines late
last year.

18. Other applications
• Clothing
making clothes of desired designs and materials, not at all necessary to bulk
produce it.
• Archeology and palaeontology
reconstructing fossils and replicating ancient and priceless artifacts
• Space Exploration
reduction in pay load
• Forensics
reconstructing bones and body parts in forensic pathology, and reconstructing
heavily damaged evidence acquired from crime scene investigations
• Printing 3d printers

19. References:
• Safari Magazine, February 2014 ,Issue no. 237
Article: Super Sawaal
• Wikipedia
• Facebook/I love science.com
• Google images