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Addi$ve Manufacturing of Dense Ceramic Parts via Direct Ink Wri$ng
of Aqueous Suspensions Lisa Rueschhoff
William Costakis, Andres Diaz Prof. Jeffrey Youngblood & Prof. Rodney Trice
6th Global Young InvesGgator Forum ICACC 2017
Na$onal Science Founda$on Graduate Research Fellowship Program (GRFP)
Grant DGE-‐1333468
Army Research Office Grant #W911NF-‐13-‐1-‐0425 Dr. Michael Bakas/Dr. David Stepp
Purdue University School of Materials Engineering
Manufacturing complex-‐shaped ceramic components necessary to broaden applica$on of ceramic materials
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• Net-‐shape parts possible with fine detail • High volume and rapid producUon
Direct Ink Wri$ng Ryan Chen, LLNL (via ceramics.org)
Commercially available syringe 3d printer
HSAP Student: Alycia McEachen, Jefferson High School, Lafaye]e, IN (now Purdue Engineering Student) URAP Student:Willy Costakis, Purdue MSE (now PhD student in Purdue MSE)
*need highly-‐loaded ceramic suspension for processing
Yield-pseudoplastic
σy
Pseudoplastic (shear-thinning)
Highly-‐loaded ceramic suspensions needed for the direct-‐ink wri$ng process
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Sh
ear
Str
ess σ
Shear Rate
Newtonian Advantages • Flowable at room temperature
• Ability to use low pressure tooling • High ceramic content
• High density a_er pressureless sintering
• Low binder content • Aqueous, green processing • Rheology amenable to variety of processing methods
Aqueous ceramic suspensions =Ceramic powder (~50 vol.%)+ water +
polymer (<5 vol.%) + dispersant • Yield-‐PseudoplasUc rheology
V.L. Wiesner, J.P. Youngblood, and R.W. Trice, “Room-‐temperature injecUon molding of aqueous alumina-‐polyvinylpyrrolidone suspensions,” J. Eur. Ceram. Soc., 34 [2] 453–463 (2014).
viscosity, η
Various ceramic systems stabilized to high solids loading in water
Material Dispersant Suspension Solid Loading
Pressureless Sintered Density (%TD)
Alumina (Al2O3) Darvan 821A Up to 57 vol.% 97-‐100
Zirconium Diboride (ZrB2) Darvan 821A Up to 49 vol.% 97-‐100
Boron Carbide (B4C) PEI Up to 56 vol.% ~ 83
Silicon Nitride (Si3N4) Concrete AddiUves Up to 47 vol.% ~ 95
Green Body B4C (cast)
V.L. Wiesner, L.M. Rueschhoff, A.I. Diaz-‐Cano, R.W. Trice, and J.P. Youngblood, “Producing Dense Zirconium Diboride Components by Room-‐Temperature InjecUon Molding of Aqueous Ceramic Suspensions,” Ceram. Int., In review (2015). M. Acosta, V.L. Wiesner, C.J. MarUnez, R.W. Trice, and J.P. Youngblood, “Effect of Polyvinylpyrrolidone AddiUons on the Rheology of Aqueous, Highly Loaded Alumina Suspensions,” J. Am. Ceram. Soc., 96 [5] 1372–1382 (2013).
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Pressureless Sintered ZrB2 (IM)
Pressureless Sintered Al2O3 C-‐Ring (IM)
0.5 in
Green Body Si3N4 (cast) Val Wiesner Andres Diaz
Material choices for addi$ve manufacturing process
Boron Carbide
S. Leo, C. Tallon, N. Stone, and G. V Franks, J. Am. Ceram. Soc., 97 [10] 3013–3033 (2014). M.W. Barsoum, Fundamentals of Ceramics. Taylor & Francis Group, LLC, 2003. Callister Jr., W. D., Materials Science and Engineering An IntroducGon. John Wiley & Sons, Inc.: 2007; Vol. 7th.
Alumina
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Andres Wed, 8:50am Salon E
• Model material: inexpensive and easy to sinter
• Low Mw Darvan 821 to disperse • Polyvinylpyrolidone (PVP, 55k g/mol) for green body strength
• Lightweight (2.52 g/cc) and high hardness -‐> light weight body armor
• Polyethyleneimine (PEI) to disperse Andres: Wed 8:50am, Salon E
Direct ink wri$ng of established aqueous suspensions as another method to produce near-‐net shapes
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• Syringe movement on x & y-‐axis • Up d = 1.26 mm • nozzle speed = 4 mm/s
• DeposiUon stage on z-‐axis
Commercially available syringe 3d printer
Rheological analysis of alumina suspensions for direct ink wri$ng
7 L.M. Rueschhoff, M.J. Michie, W.J. Costakis, J.P. Youngblood, and R.W. Trice, “AddiUve Manufacturing of Dense Ceramic Parts via Direct Ink WriUng of Aqueous Alumina Suspensions,” Int. J. Appl. Ceram. Technol., In Press (2016).
Shear Rate during forming
! = !! + !!! !
Q = volumetric flow rate [mm3/s]r = nozzle radius [mm]
* σy increases with solids loading (80 – 270 Pa)
Evaluated suspensions with 51 – 58 vol.% alumina solids loading
58%
56 55
53 51
x
ex: 55 vol.% Shear rate = 23. 2 1/s Viscosity = 12.8 Pa-‐s
(honey)
x
58 vol.% viscosity = 25.0 Pa-‐s (toothpaste)
Direct ink wri$ng of established aqueous suspensions as another method to produce near-‐net shapes
* 55 vol.% suspension shows the most uniformity in deposited layers
slumping due to low yield stress
Up clogging and non-‐uniform layers due to high viscosity
L.M. Rueschhoff, M.J. Michie, W.J. Costakis, J.P. Youngblood, and R.W. Trice, “AddiUve Manufacturing of Dense Ceramic Parts via Direct Ink WriUng of Aqueous Alumina Suspensions,” Int. J. Appl. Ceram. Technol., In Press (2016).
σy = 157 Pa
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Green Body Sintered at 1600° C to 98% TD
layer 1
layer 2
5 μm
L.M. Rueschhoff, M.J. Michie, W.J. Costakis, J.P. Youngblood, and R.W. Trice, “AddiUve Manufacturing of Dense Ceramic Parts via Direct Ink WriUng of Aqueous Alumina Suspensions,” Int. J. Appl. Ceram. Technol., In Press (2016).
Alumina specimens sintered to high density with no porosity or delamina$on between layers
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Op$miza$on of boron carbide for direct wri$ng
10 W.J. Costakis, L.M. Rueschhoff, A.I. Diaz-‐Cano, J.P. Youngblood, and R.W. Trice, “AddiUve manufacturing of boron carbide via conUnuous filament direct ink wriUng of aqueous ceramic suspensions,” J. Eur. Ceram. Soc., 36 [14] 3249–3256 (2016).
• Suspensions up to 56 vol.% ceramic solids loading studied • PEI with varying molecular weight (25,000 g/mol and 750,000 g/mol) used as dispersant and rheological modifier
Direct wri$ng suspension rheology op$mized for maximum shape reten$on
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*Op$mal
σy = 122 Pa
σy = 83 Pa
σy = 24 Pa
σy = 20 Pa
Low σy = unable to support addiUonal layers/retain shape
clogging of nozzle and warpage of green body parts
(Polyethylenimine)
Cross secUon of B4C green body
W.J. Costakis, L.M. Rueschhoff, A.I. Diaz-‐Cano, J.P. Youngblood, and R.W. Trice, “AddiUve manufacturing of boron carbide via conUnuous filament direct ink wriUng of aqueous ceramic suspensions,” J. Eur. Ceram. Soc., 36 [14] 3249–3256 (2016).
Direct wri$ng suspension rheology op$mized for maximum shape reten$on
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inset top view of specimen is at 5x smaller magnificaUon W.J. Costakis, L.M. Rueschhoff, A.I. Diaz-‐Cano, J.P. Youngblood, and R.W. Trice, “AddiUve manufacturing of boron carbide via conUnuous filament direct ink wriUng of aqueous ceramic suspensions,” J. Eur. Ceram. Soc., 36 [14] 3249–3256 (2016).
*Op$mal
Near-‐net shaped B4C specimens produced via direct wri$ng
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b)
WC from milling media
10 mm 1 mm
Layer 3
Layer 2
Layer 1
30 μm
• B4C parts sintered at 2000 ° C for 1 hr in Ar atmosphere without applied pressure
• no porosity or delaminaUon between layers
• porosity and WC observed in microstructure
• Sintered density ~82% TD (accounUng for 2.7 vol.% WC)
W.J. Costakis, L.M. Rueschhoff, A.I. Diaz-‐Cano, J.P. Youngblood, and R.W. Trice, “AddiUve manufacturing of boron carbide via conUnuous filament direct ink wriUng of aqueous ceramic suspensions,” J. Eur. Ceram. Soc., 36 [14] 3249–3256 (2016).
Alignment of both: SiC whiskers: 10 μm avg. length C-‐fiber: 220 μm avg. length
Exploring alignment of short-‐fiber composites via direct ink wri$ng
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B.G. Compton, J. A. Lewis, “3D-‐prinUng of lightweight cellular composites,” Adv. Mater., 26 [34] 5930–5935 (2014).
Direct wri$ng Alumina + C-‐fiber suspensions to visualize alignment
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52 vol.% Alumina aqueous suspension 9 vol.% C-‐fiber (100 – 200 μm in length)
1” x 1” square
20+ layers before slumping
In collaboraUon with NASA Glenn
nozzle diameter = 0.60 mm speed = 25 mm/s pressure = 20 psi
slumping when a]empUng 10+ layers
Observed carbon fiber alignment in direc$on of deposi$on during wri$ng
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1 mm
1 mm
0.5 mm
nozzle dia = 0.60 mm white matrix = Alumina black fibers = C-‐fiber (length ~100 – 200 μm)
0.5 mm
deposiUon direcUon
deposiUon direcUon
Side View Cross sec$on
Comparison to syringe-‐style 3D printer with larger nozzle diameter
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d = 0.60 mm 25 mm/s
d = 1.26 mm 4 mm/s
52 vol.% Alumina aqueous suspension 9 vol.% C-‐fiber
*lower viscosity at higher shear rate = less shape retenGon
1mm
0.5 mm
Preliminary direct ink-‐wri$ng of silicon nitride suspensions
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• 45 vol.% silicon nitride suspension • nozzle
diameter = 0.60 mm speed = 20 mm/s
1 cm
In collaboraUon with NASA Glenn
S8 Symposia Wed 9:40am, Salon B
Summary: robust parts created via direct wri$ng of aqueous suspensions
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Syringe-‐style 3D printer modified to direct ink write aqueous ceramic suspensions
Robust parts made of alumina and boron carbide via direct ink wriUng
Boron Carbide
Alumina
Rheology tailored for DIW to minimize slumping and other defects
Preliminary experiments show fiber-‐filled ceramic suspensions can be
Thank You!
Na$onal Science Founda$on Graduate Research Fellowship Program (GRFP)
Grant DGE-‐1333468
Army Research Office Grant #W911NF-‐13-‐1-‐0425 Program Manager: Dr. Michael Bakas/Dr. David Stepp
Ques$ons?
ACerS Engineering Ceramics Dr. Valerie Wiesner Alycia McEachen
