STEREOLITHOGRAPHY

2. STEREOLITHOGRAPHY
BY
G.NAVEEN KUMAR
ROLL NO:16711A0310
MECHANICAL DEPARTMENT

3. CONTENT
HISTORY OF STEREOLITHOGRAPHY
INTRODUCTION
WORKING PRINCIPLE
APPLICATIONS
PROCESS PARAMETERS
ADVANTAGES
DISADVANTAGES

4. HIDEO KODAMA
Stereolithography or "SLA"
printing is an early and
widely used 3D printing
technology. In the early
1980s, Japanese researcher
Hideo Kodama first
invented the modern layered
approach to
stereolithography by using
ultraviolet light to cure
photosensitive polymers

5. INTRODUCTION
DEFINITION
Stereolithography (SLA)The SLA process utilizes a vat of liquid photopolymer resin cured by ultraviolet
laser to solidify the pattern layer by layer to ‘print’ a solid 3D model. The model is built one layer at a
time, as per the 3DCAD model.
 It is a additive manufacturing process
 Stereolithography one of the several methods used to create 3D-printed objects
 It's the process by which a uniquely designed 3D printing machine, called a stereolithograph
 Stereolithography is also known as optical fabrication, photo solidification, solid free form
solidification and solid imaging.

6. WORKING
 As is the case for many additive manufacturing processes, the first step consists of designing a 3D
model through CAD software
 The laser “draws” the first layer of the print into the photosensitive resin.
 Wherever the laser hits, the liquid solidifies
 The laser is directed to the appropriate coordinates by a computer-controlled mirror.
 Most desktop SLA printers work upside-down
 That is, the laser is pointed up to the build platform, which starts low and is incrementally raised.
 The platform is raised according to the layer thickness (typically about 0.1 mm)

7. STEREOLITHOGRAPHY DIAGRAM

8. RESINS
SLA uses a UV laser to cure liquid resin into hardened plastic in a process called
photopolymerization.
Different combinations of the monomers, oligomers, photoinitiators, and various other
additives that comprise a resin result in different material properties.

9. POST PROCESSING
After finishing the material polymerization,
the platform rises out of the tank and the
excess resin is drained.
At the end of the process, the model is
removed from the platform, washed of
excess resin, and then placed in a UV oven
for final curing.
Post-print curing enables objects to reach the
highest possible strength and become more
stable.

10. LOW FORCE
STEREOLITHOGRAPHY
The basic idea that goes behind the
development of this Low Force
Stereolithography methodology is
that the force exerted by the printer
on the material during the printing
process should be minimal.
A completely new redesigned
optics engine called Light Processing
Unit (LPU) is used.
It makes the beam pass through a
spatial filter and further towards a
fold mirror and a parabolic mirror
https://youtu.be/vZW1fOIgcWU

11. Materials used in SLA
 Accura 25
 Accura 60
 Accura Bluestone
 Visijet tough
 Accura Amethyst
 Visijet white
VisiJet SL Tough (SLA). Plastic / General Purpose / Tough and Durable. Ultra-tough grey plastic that resists breakage and handles challenging functional
VisiJet SL Tough (SLA). Plastic / General Purpose / Tough and Durable. Ultra-tough grey plastic that resists breakage and handles challenging functional

12. PROCESS PARAMETERS
Minimum Wall thickness: 0.8 mm
Minimum details size: 2 mm (for text/ hole diameters etc)
Layer thickness: 0.05 mm – 0.1 mm
Max dimensions: 650 x 650 x 450 mm
Standard Accuracy: ± 0.2% (with lower limit on ± 0.2 mm). Dimensions tend to change with exposure
to direct sunlight or another UV source
Lead Time: Minimum 2 working days for despatch
Surface finish: Smooth, with tiny visible layers
Laser Scan speed: 500 to 2500 m/sec

13. APPLICATIONS
 Patterns for investment casting
 Functional testing prototypes
 Low volume/ limited edition products especially for complex geometries
 Visual prototypes for photo shoots and market testing
 Dental/ jewelry/ art and other sectors which require high detailing and finish

14. Medical application

15. ADVANTAGES
 Prototypes and designs made with
stereolithography are strong enough to be
machined
 Parts made with stereolithography have good
functional surface quality.
 High quality surface finish can be achieved
 SLA process can build complicated parts
DISADVANTAGES
 Unit product
 Only works with photopolymer materials
 Stereolithography only works with photopolymer
materials
 https://youtu.be/vuauCJIXpzo

16. THANK YOU