3. 3
Introduction
● Additive manufacturing or 3D printing is a
process of making a three-dimensional solid
object of virtually any shape from a digital
model
● 3D printing is achieved using an additive
process, where successive layers of material are
laid down in different shapes
● Printed solid model was made in 1981
4. 4
Principles : Modeling
● Takes virtual blueprints from computer aided
design (CAD)
● “Slices” them into digital cross-sections
● It is a WYSIWYG process where the virtual
model
● A standard data interface between CAD
software and the machines is the STL file
format.
5. 5
Principles : Printing
● Reads the design from an .stl file and lays down
successive layers of liquid or materials
● Ability to create almost any shape or geometric
feature
● Printer resolution describes layer thickness
● Can take anywhere from several hours to
several days
● Injection molding and Additive manufacturing
6. 6
Manufacturing : Extrusion deposition
● uses a plastic filament or metal wire that is wound on a
coil and unreeled to supply material to an extrusion
nozzle
● The nozzle heats to melt the material and can be moved
in both horizontal and vertical directions by a
numerically controlled mechanism that is directly
controlled by a computer-aided manufacturing (CAM)
software package.
● The model or part is produced by extruding small beads
of thermoplastic material to form layers as the material
hardens immediately after extrusion from the nozzle.
Stepper motors or servo motors are typically employed
to move the extrusion head.
7. 7
Extrusion Deposition : Materials
● Various polymers are used, including acrylonitrile
butadiene styrene (ABS), polycarbonate (PC),
polylactic acid (PLA), high density polyethylene
(HDPE), PC/ABS, and polyphenylsulfone (PPSU).
● In general the polymer is in the form of a filament,
which can be fabricated from virgin resins or from
post-consumer waste by recyclebots.
● FDM usually cannot produce stalactite-like structures
(Shape Restriction)
9. 9
Theories
● Stereolithography
position a perforated platform just below the surface of a
vat of liquid photopolymer. A UV laser beam then traces
the first slice of an object on the surface of this liquid,
causing a very thin layer of photopolymer to harden. The
perforated platform is then lowered very slightly and
another slice is traced out and hardened by the laser.
Another slice is then created, and then another, until a
complete object has been printed and can be removed from
the vat of photopolymer, drained of excess liquid, and
cured. Stereolithographic printers remain one of the most
accurate types of hardware for fabricating 3D output
10. 10
Theory : DLP projection
● Selective solidification of a tank of liquid
● Projector to solidify object layers one complete
cross-section at a time
12. 12
Theory : Polyjet matrix
● Forms object layers by emitting liquid
photopolymer from an inkjet-style, multi-
nozzel print head
● Each layer is printed a powerful UV light is
then used to set it solid before the next layer is
printed
● up to 14 of 120 potential materials to be printed
at the same time
14. 14
Binder jetting
● creates object layers by selectively sticking together
successive layers of a powdered build material
● a glue or 'binder' is jetted from an inkjet style print
head to stick together successive powder layers
● gypsum-based composite
● build objects by sticking together plastic powders,
sand or even metals.
● final object is used as a mould in '3D sandcasting',
with molten liquid metal poured into it
16. 16
Application : Industrial uses
● Rapid prototyping : Car and other industrial
product design
● Rapid manufacturing : Production within no
time
● Mass customization : Every inch Customization
● Mass production
21. 21
Application : Domestic and hobbyist uses
● Design
● Parts replacement
● Personal touch
Fig 10. Custom Guitars
22. 22
Challenges
● Materials ( What can be used? )
● Cost (Can General people afford it? )
● Accessibility ( Who can access it? )
● Illegal Object ( For what purpose? )
23. 23
3D Printer : Weapon Issue
● blueprints for the first "completely" 3D-
printable gun
● Other types of weapon be printed ?
Fig 12. Printed Gun
24. 24
Future
● The Third Industrial Revolution:
“ We are all designers now. We might as well
get good at it. ” -Chris Anderson
3D printing is considered distinct from traditional machining techniques, which mostly rely on the removal of material by methods such as cutting or drilling (subtractive processes) Then limited to industrial use only but recently It can be used for personal purpose Charles Hull inventor of 3d printer
An STL file approximates the shape of a part or assembly using triangular facets. Smaller facets produce a higher quality surface. PLY is a scanner generated input file format, and VRML (or WRL) files are often used as input for 3D printing technologies that are able to print in full color.
Typical layer thickness is around 100 micrometres (0.1 mm) The particles (3D dots) are around 50 to 100 micrometres (0.05–0.1 mm) in diameter depending on the method used and the size and complexity of the model.