In material extrusion process, the material is fed in coil form through a heated and pressurized nozzle which is known as an extruder. The extruder is capable of moving in the horizontal plane and vertical plane. The flow rate of material and pressure are kept constant through the process. After one layer of deposition, either the extruder moves in an upward direction or the base moves in a downward direction so that the next layer can be deposited. The material is loaded in solid-state. In the extruder, it transformed into semisolid state and again becomes solid after bonding with the previous layer. We can divide the full extrusion process into several steps: 1. Material loading. 2. Transforming material in liquid form. 3. Applying pressure to the material in the nozzle. 4. Extrusion of material. 5. Solidification of material. 6. Deposit the material according to design. 7. Material bonding. 8. Supporting the structure.

1. Operating principle of
Fused deposition
modeling (FDM)

2. Materialloading andapplying
pressure
Transforming materialin
liquid form
Extrusion of material
Solidificationof material
01
02
03
04
Step of operating principle
Deposition of materialaccordingto
design
Materialbonding
Supporting thestructure
05
06
07

3. Material loading and applying pressure
01
Form of material:
Pellet Powder Continuesfilament

4. Material loading and applying pressure
01
Gravitationalforceand compressed gas Screw typepropelling system

5. Transformingthe material intoliquid form
02
Heat applying:
Toohigh temperaturecan
degradethematerial
Toolow temperaturecanmake
depositionofthe material

6. Extrusionof material
03
Higherdiameter
More material flow
Lower precision
Lower diameter
Less material flow
More precision
Multiple extruder

7. Solidification of material
04
Porosity can occurs Temperature difference is kept low

8. Deposition of material according to design
05

9. Material bonding
06
To low energy causesweakbond To highenergy causes movement
ofmaterial

10. Supportingthe structure
07
Forsimilar supportingmaterial
single extruderis used.
Forsecondarysupportingmaterial
multiple extruderis used.
Figure:Multiple extruderis used.

11. Limited layer
thickness
Higher building time
Limited shapes of Nozzles
Lower accuracy rate
01
02
03
04
Drawbacks of Material
Exrtusion(FDM)
Low-speed channels
Requires large
bandwidth
Requires carrier wave .
05
06
07
087
Affected by wideband
fading

12. 1.Limited layer thickness
01
Fig: Expensive 3D printer machine
Higherbuildingtime
02
Dynamic co-
ordination

13. Limited shapes of Nozzles
03
Lower accuracy rate.
04
Fig: Nozzles of 3D printing
machine
Fig: Driver belts

14. Low-speed channels
05
Requires large bandwidth.
06

15. 07
Requires carrierwave
08
Affected by wideband fading.
Before After

16. Drawbacks
 Layer thickness option of 0.078mm is only available in the expensive machines.
 Building time required in this level of precision is much higher. Besides, it has no
dynamic co-ordination.
 As all nozzles are circular in shape, it is impractical to use for drawing sharp
external corners.
 Lower cost machines use belt drivers which makes flexing in belt which reduces
the accuracy
 It is only suitable when very few amount of low-speed channels are required.
 FDM system requires a large amount of bandwidth but the full capacity of the
channel cannot be used on this system and a large number of modulator and filter
are required here.
 FDM channel can get affected wideband fading.
 It needs a carrier wave or carrier signal for transmission.

17. Conclusion
1. The main consideration points in choosing a machine are generally costs
of the 3D printer, speed of the machine, choice and cost of the materials,
choice and cost of the printed prototype, and last of all color capabilities.
2. We can get high precision of regardless of uneven heating or bowed
build plate
3. Sensors ensure the print head is always moving parallel to build plate.
4. No wasting time fiddling with the bed and Z height, So it’s easy
FOR inexperienced machinists to operate.
5. Hence we are intended to produce low cost 3D printer for all with an
estimated cost of 11000 INR

18. THANK YOU