Eric MacDonald - 3D Printing of Multi-Functional Structures

1. Progress in 3D Printed Multi-functionality
Eric MacDonald, PhD PE
Friedman Chair for Manufacturing, Youngstown State University
Associate Director, W. M. Keck Center for 3D Innovation, UTEP

2. Outline

3. London Museum of Science and Manchester Museum of Industry in exhibit
3D Printed Gun from University of Texas Law Student (confiscated)
3D Printed Satellite from UTEP / UNM COSMIAC
Intro: 3D Printing in International Spot Light

4. Intro: ASTM F42 Categories
■ Vat Photopolymerization
■ Material Extrusion
■ Powder Bed Fusion
■ Material Jetting
■ Binder Jetting
■ Sheet Lamination
■ Directed Energy Deposition
AM Technologies
Available within the
UTEP Keck Center
Major Research in Multifunctional 3D
Processes and Applications
Major research in Arcam EBM
Investing in Lasers – SLM, Aconity
Recent investment in Binder jetting
ExOne – ceramics, metals, RF

5. Intro: ASTM F42 Categories
■ Vat Photopolymerization
■ Material Extrusion
■ Powder Bed Fusion
■ Material Jetting
■ Binder Jetting
■ Sheet Lamination
■ Directed Energy Deposition
AM at YSU and the
America Makes
Innovation Factory
Youngstown, OH
Research focus on smart
tooling, sand casting, computer
vision for closed loop control,
metal repair,.
Starting 3D printed electronics.

6. Intro: Vat Photopolymerization
■ AM process with a vat of photocurable polymer cured
selectively by laser or projector.
■ Benefits
• Surface finish
• Resolution (75 microns)
• uSL (5 microns)
• Ambient processing
■ Issues
• Materials limitations
• Post cleaning

7. Intro: Materials Extrusion
■ AM process that selectively extrudes a thermoplasitc
■ Based on Stratasys FDM patents (expired patent –> proliferation)
• Most popular
■ Benefits
• Office friendly
• DIY community
• Large volume
■ Issues
• Resolution
• Surface finish
• Z axis anisotropy

8. Intro: Powder Bed Fusion
■ AM process where thermal energy selectively melts/sinters
the top surface of a powder bed.
■ SLS, SLM, DMLS, EBM
• Polymers, metals & ceramics
■ Benefits
• Multiple materials (metals, nylon)
• Strength
• Fully dense
■ Issues
• Wasted powder
• Powders processing

9. Intro: Materials Jetting
■ AM process in which photocurable material is inkjetting
and immediately cured with a UV lamp
• Wax or Photopolymers
• Multiple nozzles
• Single nozzles
■ Benefits
• Multiple colored materials
• Ink jet resolution
■ Issues
• Materials limitations

10. Intro: Binder Jetting
■ AM process depositing binder with inkjetting onto a powder
bed and thermally cured – often infiltrated for full density.
■ Zcorp (Dead)
• ExOne
• Voxeljet
• HP Fusionjet ?
■ Benefits
• Multiple colors per layer
• Wide range of materials
■ Issues
• Post furnace cycle
• Strength (Z Corp)

11. Intro: Sheet Lamination
■ AM process in which laminate material is bonded and
selectively removed
• Paper – glue
• Plastic – glue / heat
• Metal – UC welding
■ Benefits
• Materials choices
– Aluminum (UC)
• Strength (UC)
■ Issues
• Waste
• Additional steps

12. Intro: Directed Energy Deposition
■ AM process in which material and energy are applied
coincidently to the layer.
■ Benefits
• Feature addition and repair
• Wire & Powder Materials
• Lasers & Electron Beams
■ Optomec LENS –
– Good resolution but slower
■ Sciaky
– Large build (19’x4’x4’)
– Fast (20 Lbs / hour)
– Lower resolution
■ Ambit

13. UTEP closer to San Diego than Houston
YSU < six hours from NYC, Chicago, Pitt,
Cleveland, DC, Philly
Intro: Where are El Paso and Youngstown?

14. • Founded in 2000 – 13,000 sq. ft. facility with over 50 3D printers
• R&D projects with over 100 industrial clients and ten federal agencies
• More than 50 student researchers and seven full-time staff
• Broad and expanding patent portfolio
• Everything we do uses 3D printing technologies
14
Intro: UTEP’s Keck Center

15. • Founded in 2000 – 13,000 sq. ft. facility with over 50 3D printers
• R&D projects with over 100 industrial clients and ten federal agencies
• More than 50 student researchers and seven full-time staff
• Broad and expanding patent portfolio
• Everything we do uses 3D printing technologies
15
Intro: YSU’s CIAM Center

16. Intro: 3D Printing in International Spot Light
http://www.journals.elsevier.com/additive-manufacturing/
■ Ryan Wicker Editor in Chief
■ Eric MacDonald, Deputy Editor
■ Mireya Perez, Managing Editor
■ Introducing fast-publication, science-based,
peer-reviewed journal for academia / industry
■ Inaugural issue in Summer 2014
■ Topics:
• Design and Modeling
• AM processes and process enhancement
• Multiple and novel materials
• Special applications with multi-functionality

17. Materials: Twin Screw Extruder
Matrix
Material
Additives
Extruder Unit
Extruded Composites
3D Printed Structures
3D Printer
Extrude thermoplastic feedstock (3D printer specialty ink):
• Increase Material Strength, Hardness, Flexibility, Stretchability
• Optimize Permittivity / Permeability
• Increase Thermal Conductivity
• Improve Radiation Shielding
• Tungsten impregnation
• High Density Polyethylene (HDPE)

18. Materials: Heavy Metal Composites
• Tungsten powder in Polycarbonate
– Trade-off between:
• Weight
• Strength
• Thermal / electrical conductivity
• Radiation attenuation
– 3D printed geometries for shielding
– Optimize unused volume for protection
Radiation shielding

19. Additives Permittivity Extruded
CaTiO3 165 Yes
SrTiO3 233 Yes
TiO2, anatase 48 Yes
TiO2, rutile 114 Yes
NaCl 5.9 Yes
Fe3O4 Permeability Yes
Tungsten Rad. Shield Yes
Zeonex Low Loss Yes
Extrusion of E&M Polycarbonate
Goals: Radiation Shielding
Low Loss Antennas
Electrically Large Antennas
Electromechanical Devices
Materials: RF and Magnetic Materials

20. Materials: Flexibility / Stretchability
• UTEP Proprietary Polymer Blend
– ABS/SEBS Blend
– Tunable strain
– Wires embed structurally
ABS Grade MG94 blended with Kraton SEBS-g-MA. Tunable strain from 3.32 ± 0.7 % to 1506.57 ± 90.1%

21. Complementary Manufacturing
3D Printing for Dielectric Structures
Enhanced
thermoplastics
Technology: 3D Printed Electronics
In low Earth Orbit
Ceramics
Photo-
polymers
wires dispensing
machining
lasers
motorsconformal
3d sensors
3d sensors
Satellites

22. Technology: Ultra sonic / thermal embedding

23. copper wire
3D printed thermoplastic substrate
Laser Micro-Welding
Technology: Replacing Conductive Inks
Replace inks with bulk copper:
- High conductivity
- Good density (80 micron wires)
- Low cost relative to silver inks
- Laser welding for connections
100 microns

24. anvil double-sided tape
ABS substrate
metal mesh
polyimide film
vertically
oscillating
horn
scanning direction
0
5
10
15
20
25
30
35
40
45
AverageYieldStrength(MPa)
Theoretical
Actual
Technology: Serendipitous enhancements
Mechanical reinforcement:
- Essentially a composite
- Structurally integrated wires
- Improving anisotropy

25. Technology: Milled Foils for Intricate Patterns
0.075”
0.080”
0.020”
0.125”35 micron thick copper foil is
equivalent to PCB plating.
Smooth surface is well-suited
for RF apps at high frequency.

26. Technology: Original Multi3D Manufacturing

27. Technology: Independent Wire Embedding
• Lockheed Martin / Wolf Robotics Factory of the Future
• Point wise Composition Control
• “Borrowing” UTEP Wire Embedding
• Displayed at Defense Manufacturing Conference Exhibition
600 micron
diameter
copper wire

28. Technology: Next Gen Multi3D
Foil
applica)on
will
milling
• Consolidated
single
gantry
fabrica)on
system.
• Tool
exchanger
• Five
degrees
of
freedom
• 200
°C
Build
Chamber
• Full
opera)on
on
schedule
for
Oct
16
Pellet
fed
extrusion
/
tool
exchange
Wire
embedding

29. Technology: Big Area AM (BAAM) with Multi3D
Grant
for
Integra)ng
hybrid
wire
embedding
into
Oak
Ridge
technology
Base
fabrica)on
born
from
Oak
Ridge
and
LMC.
Commercialized
by
Cincinna),
Inc
and
car
design
and
fabrica)on
by
Local
Motors,
Inc

30. Demonstrations: Conformal Electronics

31. Demonstrations: Satellite Electronics
To avoid
this wiring
clutter…
Wiring bus in structure
Bus connector
Solar panels
in walls

32. Demonstrations: 3D Printed Propulsion
• Busek Pulsed Plasma Thrusters
• requiring high voltage (1-10kV)
• non-toxic Teflon propellant
• Dielectric strength and leakage testing
• Propulsion (micro-newton) testing at
Glenn NASA.
Propulsion Test Plate

33. Demonstrations: 3D Printed Thermal Mgmt
Textured Radiator
intended for space
applications
3D Printed Graphite

34. 34
1 2 3 4 5 6 7 8 9 10
30−
20−
10−
0
Attached Balun
Mesh Balun
Embedded Balun
Spiral Iteration 2 Return Loss
Frequency [GHz]
S11[dB]
-90 -80 -70 -60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60 70 80 90
-18
-16
-14
-12
-10
-8
-6
-4
-2
0
Azimuth (degrees)
NormalizedMagnitude(dB)
Radiation Pattern
Archimedian Spiral - Embedded Balun (f = 2.3 GHz)
LHCP
RHCP
-90 -80 -70 -60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60 70 80 90
-22
-20
-18
-16
-14
-12
-10
-8
-6
-4
-2
0
Azimuth (degrees)
NormalizedMagnitude(dB)
Radiation Pattern
Archimedian Spiral - Attached Balun (f = 2.3 GHz)
LHCP
RHCP
-90 -80 -70 -60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60 70 80 90
-14
-12
-10
-8
-6
-4
-2
0
Azimuth (degrees)
NormalizedMagnitude(dB)
Radiation Pattern
Archimedian Spiral - Mesh Balun (f = 2.3 GHz)
LHCP
RHCP
Demonstrations: Archimedes Antenna Results

35. Demonstrations: Conformal Patch Antennas
Again,
Patch
A
was
designed
for
5.85
GHz,
and
Patch
B
for
5.65
GHz
with
no
fringing
factor.
Measurement
showed
the
actual
resonances
to
occur
at
6.27
GHz
and
6.18
GHz
although
the
S11
curve
was
much
higher
as
compared
to
the
foil
patches.
A
B
5 5.2 5.4 5.6 5.8 6 6.2 6.4 6.6 6.8 7 7.2 7.4 7.6 7.8 8 8.2 8.4 8.6 8.8 9
30−
20−
10−
0
Mesh Patch A
Mesh Patch B
Conformal Mesh Patch Antennas
Frequency [GHz]
S11[dB]

36. Demonstrations: 3D Printed UAVs

37. Demonstrations: 3D Printed Motor

38. Computer Vision: Defects Easily Identified
Precise geometric data
is captured from image
for comparison against
GCODE and CAD.

39. Computer Vision: Fourier Analysis
Frequency content describes roughness of surfaces or uniformity of powder.
Smooth Surfaces
Rough Surfaces
2D Freq Spectrum

40. Computer Vision: Video Feature Tracking
Tracking of heads, tips, salient process features.

41. Computer Vision: Electron Beam Tracking
Geographical data collected from real
time in IR video of electron beam
melting of one layer of a cylinder in an
evacuated build chamber.
Detecting difference from frame to
frame.
Fumes causing false detections but
easily filtered.
Identical video with persistent
dots. 4X speed.

42. Computer Vision: Thermographic Evaluation
Open Source computer vision, one image per layer.
Standard camera and $200 FLIR Lepton camera.
Tool path modified to hide “hot” extruder after each layer.

43. 2D side profiling with high resolution geometry verification.
Computer Vision: Geometric Verification

44. Computer Vision: Debris Detection

45. Precise pixel-level measurement of existing layers during print.
Virtual and dynamic calipers. Three layers are
monitored for width
changes during
subsequent layers
Computer Vision: Layer Width Measurement

46. Conclusion: Campus Architecture
Inspired by a 1916 National Geographic
photo essay of the Kingdom of Bhutan
Buddhist Himalayan Architecture
When YSU president Jim Tressel speaks,
I instinctively want to deliver a open field tackle.
GO PENGUINS!
UTEP
YSU