This document discusses various 3D printing techniques. It describes fused deposition modeling (FDM), which works by extruding melted thermoplastics through a nozzle to build objects layer by layer. Direct ink writing (DIW) uses extrusion of viscous materials like hydrogels through a nozzle. Stereolithography (SLA) involves using a laser to polymerize photosensitive resins layer by layer. Selective laser sintering (SLS) uses a high-power laser to fuse powders like metals and ceramics. Particle binding techniques use liquid binders to fuse powder particles and require sintering. Inject printing (IP) involves depositing droplets that solidify to form structures. Each technique

1. 3D Printing
Commanded precinct Engineering

2. AnAdvance
Manufacturing
Technique
 Control architecture
 Control pores structure
 Custom design
 Computer Controlled

3. Classification
of 3D-Printing
techniques
Inject
Printing(IP)
Particle
Binding(PB)

4. Extrusion
Based
Techniques
 Fused deposition Modeling(FDM)
 Direct ink writing(DIW)

5. Fused
Deposition
Modeling
 A filament of desired material fed and melt by heating and extruded through
nozzle.
 Deposited layer by layer
Appliance Materials
 Polymers
 Polymers/ceramics
Accuracy
200-500um
Dependence
 Melting temperature of building material
 Too high to retain by bio molecule
Schematics of FDM

6. Direct Ink
Writing(DIW)
 Extrusion-based
 Viscous materials(referred to as a ‘‘paste’’ or an ‘‘ink’’) are extruded
through the nozzles by a compressed gas to form individual lines that
solidify onto a build plate in a layer-by-layer fashion.
Materials
 Viscous materials
 Inorganic and organic composite paste
 Hydrogels
Accuracy
(200-600)um

7. Stereolithogra
phy(SLA)
 Vat polymerization
 Promising for tissue fabrication in regenerative medicine
 A single beam laser to polymerize or crosslink a photosensitive polymer to get thin
layers of the polymer and then stacks the struts layer-by-layer.
 Porosity of scaffolds
 Pores size
 Design flexibility
 Interconnectivity
Materials
 Photo sensitive polymers
Accuracy
(10-30)um

8. Selective Laser
Sintering(SLS)
 Developed by University of Texas USA.
 Powder Based Fusion(PBF) technique.
 High-power laser used to melts the powder material.
 Laser sintered near the melting point of material to form a given 3D
Design.
 Fused layer by layer into large parts, and the scaffold is made.
Materials
 Metals
 Ceramics in fine powder form
Accuracy
(700-1000)um

9. Particle
Binding(PB)/
Binder jetting
 Developed in the early 1990s at Massachusetts Institute of
technology(MIT)
 A liquid binding solution to fuse particles together within each layer,
followed by a high-temperature sintering step to solidify the final 3D
products.
 Powder material
 Particle size
Materials
 Ceramics
Accuracy
(700-1000)um
Schematics of the mechanism

10. Inject
Printing(IP)
 Developed in 1992 at MIT
 Deposition of very small volumes of individual droplets from a nozzle onto
a printing surface with a goal of forming structures by post-printing
solidification.
Materials
 Ceramics
Accuracy
 25-100 picolitres
Advantage
 Multifunctional
Disadvantages
 Low mechanical property

11. Advantages
and
disadvantages
Technique Advantages Drawbacks
Fused deposition
modeling(FDM)
• High mechanical
properties
• Solvent not required
• Need to formed into
filament
• High temperature
required
Stereolithography(SLA) • High resolution
• Large molding products
• Extensive post
processing
• Inadequate mechanical
properties
• Toxic uncured resins
Selective laser
sintering(SLS)
• Support not required
• Process multiple
materials in single bed
• Slow
• Bulky
• Expensive
• Rough surface

12. Advantages
and
disadvantages
Technique Advantages Drawbacks
Particle binding(PB) • High mechanical
strength
• Need further sintering
step
Inject printing(IP) • Multifunctional
• high resolution,
• fast manufacturing
• Low mechanical
property
• Intrinsic inability to
deliver a continuous flow
Direct ink writing(DIW) • Easy
• Fast
• Low temperature
• Cells and bioactive
materials can be printed
• Solvent required
• Easy to sag or collapse
during printing