novel niti shape memory alloy films manfred wuttig
DESCRIPTION
NOVEL NiTi SHAPE MEMORY ALLOY FILMS Manfred Wuttig. Manfred Wuttig Tel 301-405-5212 Fax 301-314-9467 Email [email protected]. CONTENTS OF PRESENTATION Introduction Novel NiTi Films 1.One Dimensional NiTi Films 2.Gradated NiTi Films 3.NiTi (Ms1)/NiTi(Ms2) Films. - PowerPoint PPT PresentationTRANSCRIPT
NOVEL NiTi SHAPE MEMORY ALLOY FILMSManfred Wuttig
Manfred Wuttig Tel 301-405-5212 Fax 301-314-9467 Email [email protected]
CONTENTS OF PRESENTATION
Introduction
Novel NiTi Films 1. One Dimensional NiTi Films 2. Gradated NiTi Films 3. NiTi (Ms1)/NiTi(Ms2) Films
NOVEL NiTi SHAPE MEMORY ALLOY FILMSManfred Wuttig
Manfred Wuttig Tel 301-405-5212 Fax 301-314-9467 Email [email protected]
-100 0 1000
100
200
300
Flat
Corrugated
dD
ispl
acem
ent d
(m
)
Temperature (oC)
0.0 0.5 1.0 1.5 2.0 2.52.5
2.0
1.5
1.0
0.5
0.0
film
substrate
y/c
x/a
Corrugated Films - Complicated Stress Distribution
Report on ”Corrugated ” Film that can be easily analyzed
NOVEL NiTi SHAPE MEMORY ALLOY FILMSManfred Wuttig
Manfred Wuttig Tel 301-405-5212 Fax 301-314-9467 Email [email protected]
Gradated Films - Not Easy to Prepare
Report on Gradated Films prepared by varying substrate temperature
NOVEL NiTi SHAPE MEMORY ALLOY FILMSManfred Wuttig
Manfred Wuttig Tel 301-405-5212 Fax 301-314-9467 Email [email protected]
Report on “Corrugated “ Films that can be easily analyzed
NOVEL NiTi SHAPE MEMORY ALLOY FILMSManfred Wuttig
Manfred Wuttig Tel 301-405-5212 Fax 301-314-9467 Email [email protected]
“Geometrically Novel” NiTi Films
Film
Substrate
L
Wg
tstf
wf
(a) 1-D/1-D (b) 2-D/2-D (c) 1-D/2-D
NOVEL NiTi SHAPE MEMORY ALLOY FILMSManfred Wuttig
Manfred Wuttig Tel 301-405-5212 Fax 301-314-9467 Email [email protected]
(a) (b)
SampleNr.
Width of stripwf /m
Distance betweenstripsg /m
Aspect ratiotf/wf
Actual arealdensity
wf/(wf+g) [%]1 2.9 2.1 0.31 58.02 5.4 4.6 0.16 54.03 54 46 0.016 54.04 1000 1000 0.0009 50.0
NOVEL NiTi SHAPE MEMORY ALLOY FILMSManfred Wuttig
Manfred Wuttig Tel 301-405-5212 Fax 301-314-9467 Email [email protected]
Principle of measurement, the cantilever deflection is determined from the change of the resonance frequency, LC1r
L
d C
NOVEL NiTi SHAPE MEMORY ALLOY FILMSManfred Wuttig
Manfred Wuttig Tel 301-405-5212 Fax 301-314-9467 Email [email protected]
-200 -100 0 100 200 300600
700
800
900
1000
1100
1200
1300
Norm
ariz
ed d
efle
ctio
n (m
)
Temperature (oC)
Deflection of four differently patterned NiTi/Si bimorph cantilevers as a function of temperature. All bimorphs were processed simultaneously and identically. aspect ratio = 0.31 aspect ratio = 0.16 aspect ratio = 0.016 aspect ratio = 0.0009
NOVEL NiTi SHAPE MEMORY ALLOY FILMSManfred Wuttig
Manfred Wuttig Tel 301-405-5212 Fax 301-314-9467 Email [email protected]
w
fw
f
-ws-w
s
L
f
L
f
-Ls
(b)
w
s0
w
f 0
L
s < 0
L
f > 0(c)
(a)
Stress analysis of a 1-D / 2-D composite:
(a) unstressed components
(b) components stressed biaxially
(c) patterned film and substrate stressed uniaxially.
NOVEL NiTi SHAPE MEMORY ALLOY FILMSManfred Wuttig
Manfred Wuttig Tel 301-405-5212 Fax 301-314-9467 Email [email protected]
Substrate
SMA
Conceptual martensitic microstructure:biaxially, top, and uniaxially, bottom,stressed SMA films in the two phase temperature region. The light and dark sections represent martensite and austenite, respectively.
NOVEL NiTi SHAPE MEMORY ALLOY FILMSManfred Wuttig
Manfred Wuttig Tel 301-405-5212 Fax 301-314-9467 Email [email protected]
)1(E)1(E
t
t6
fs
sf2s
f'bi
0
021
021
0
0
0
0
0000
00
0000000
21
0000000
21
0
0
0
0
0
000
00000
0000000
21
0000000
21
Cantilever deflection, Stoney’s Eq.:
Martensite biaxial
Martensite uniaxial
Thermal
T
NOVEL NiTi SHAPE MEMORY ALLOY FILMSManfred Wuttig
Manfred Wuttig Tel 301-405-5212 Fax 301-314-9467 Email [email protected]
Slope of deflection
dTd
'
T tf /wf
*) Modulusterm
Strainterm
Ratio
L
'H
'
dTd
dTd
Esti-matedratioPest
Experi-mentalratioPexp
Low(Bi)
2s
f
tt6
sf
fs
EE)1()1(
T
T > AfT < As
High(Uni)
2s
f
tt6
s
f
EE
T
s
f11
0.7 0.84(A)0.85(M)
Low(Bi)
2s
f
tt6
s'f
'fs
E)1(E)1(
dTTdM )(
As <T< Af
High(Uni)
2s
f
tt6
s
f
EE'
dTTd
M)(
s
f
11 '
1.4 1.28(avg.)
Evaluation of slopes of deflection and comparison of ratios.
NOVEL NiTi SHAPE MEMORY ALLOY FILMSManfred Wuttig
Manfred Wuttig Tel 301-405-5212 Fax 301-314-9467 Email [email protected]
Report on Structurally Gradated Films prepared by varying substrate temperature
NOVEL NiTi SHAPE MEMORY ALLOY FILMSManfred Wuttig
Manfred Wuttig Tel 301-405-5212 Fax 301-314-9467 Email [email protected]
Martensite/MartensiteComposite NiTi Films
Previous Experiments Show:
The nature of the martensitic transformation depends on the deposition temperature.
Therefore:
It is possible to create martensite/martensite composites by varying the substrate
temperature during deposition.
35 40 45 500
100
200
300
400
500
double layer
385 oC
250 oC
Inte
nsity
/ Co
unts
2
NOVEL NiTi SHAPE MEMORY ALLOY FILMSManfred Wuttig
Manfred Wuttig Tel 301-405-5212 Fax 301-314-9467 Email [email protected]
250
385
385
385
semi-continuous
discontinuous
continuous
t [min]0 50 100
250
250
T[oC]
10
Variation of the substrate temperature during sputter deposition of the films.
top, semi-continuous,center, discontinuous,bottom, continuous
NOVEL NiTi SHAPE MEMORY ALLOY FILMSManfred Wuttig
Manfred Wuttig Tel 301-405-5212 Fax 301-314-9467 Email [email protected]
-150 -100 -50 0 50 100 150 200
0
2
4
6
8
10
12
14
Q-1 x
10-4
Temperature [oC]
Internal Friction of NiTi double layer film
Deposited while semi-continuously cooling, ;
Single layers deposited at250 deg C,
385 deg C,
-100 0 1000
4
8
12
-100 0 100 -100 0 1000
4
8
12
+
Manfred Wuttig Tel 301-405-5212 Fax 301-314-9467 Email [email protected]
Natural and Artificial MultiferroicsNew UMD-based MURI
SMA/SMA Composite With Large Damping SMAs display large damping, up to 50%, at large amplitudes of vibration,
useful for mitigation of earth quake damage -scale R-M SMA Composites display 11% damping at small amplitudes,
useful for mitigation of (small amplitude) mechanical noise Craciunescu/Wuttig, J. Thin Solid Films
Rhombohedral Phase Monoclinic Phase -Scale R-M Composite
=Temperature [C]
Dam
ping
Q-1 [%
] Dam
ping Q-1 [%
]
NOVEL NiTi SHAPE MEMORY ALLOY FILMSManfred Wuttig
Manfred Wuttig Tel 301-405-5212 Fax 301-314-9467 Email [email protected]
/g/g
21122211)2(L)1(L)0,0,0(g)2,1,(g
2120
22/g2
021/g2
)21(1Q
Analysis of Enhanced Damping
NOVEL NiTi SHAPE MEMORY ALLOY FILMSManfred Wuttig
Manfred Wuttig Tel 301-405-5212 Fax 301-314-9467 Email [email protected]
-150 -100 -50 0 50 100 150 200-100
0
100
200
300
400
500
Disp
lace
men
t [
m]
Temperature [oC]
Displacement curves of the NiTi double layer films;
Depositions on cooling; semi-continuous, discontinuous, continuous.
Depositions on heating; semi-continuous, discontinuous, continuous.
-200 -100 0 100 200
-0.03
-0.02
-0.01
0.00
M/M
Temperature [oC]-100 0 100 200
-0.015
-0.010
-0.005
0.000
0.005
M/M
Temperature [oC]
Modulus curves for the double layer film deposited on cooling and heatingleft, cooling: semi-continuous, discontinuous, continuous right, heating: semi-continuous, discontinuous, continuous
NOVEL NiTi SHAPE MEMORY ALLOY FILMSManfred Wuttig
Manfred Wuttig Tel 301-405-5212 Fax 301-314-9467 Email [email protected]
NOVEL NiTi SHAPE MEMORY ALLOY FILMSManfred Wuttig
Manfred Wuttig Tel 301-405-5212 Fax 301-314-9467 Email [email protected]
Heating(H)
Cooling(C)
T
Ms385
Ms250
Tx
t
T
Ms385
Ms250
Tx
t
T
Ms385
Ms250
Tx
t
Substrate
t
250oC layer385oC layer
Substrate
t
385oC layer250oC layer
Tx > Ms250, Ms385 Ms250 < Tx < Ms385 Tx < Ms250, Ms385
T
Ms385
Ms250
Tx
t
Dis
cont
inuo
us D
epos
ition
T
Ms385
Ms250
Tx
t
T
Ms385
Ms250
Tx
t
Bimorph Temperature(Tx)
Both layers inaustenitic state
Top layer transformsunder constraintfrom one side
Bottom layertransforms under
constraint from oneside
Both layers inaustenitic state
Bottom layer transformsunder constraint from
both sides
Top layer transformsunder virtually no
constraint
Deposition Type
No ModulusDefect
NOVEL NiTi SHAPE MEMORY ALLOY FILMSManfred Wuttig
Manfred Wuttig Tel 301-405-5212 Fax 301-314-9467 Email [email protected]
Heating(H)
Cooling(C)
Substrate
t
250oCt layer
385oCt layer
Tx > any Mst Tx = Mst Tx < any Mst
Con
tinuo
us D
epos
ition
Bimorph Temperature (Tx)
All t layers inaustenitic state
t layers transformcontinuously under
constraint from one side
All layers inmartensitic state
All t layers inaustenitic state
t layers transformcontinuously under
constraint fromboth sides
Top t layer transformsunder virtually no
constraint
Deposition Type
Substrate
t
385oCt layer
250oCt layer
T
Ms385
Ms250
Tx
t
T
Ms385
Ms250
Tx
t
tt T
Ms385
Ms250
Tx
t
T
Ms385
Ms250
Tx
t
T
Ms385
Ms250
Tx
t
t T
Ms385
Ms250
Tx
t
t
LargeDisplacement
LargeDamping
NOVEL NiTi SHAPE MEMORY ALLOY FILMSManfred Wuttig
Manfred Wuttig Tel 301-405-5212 Fax 301-314-9467 Email [email protected]
SUMMARY
Two Kinds of Novel NiTi Films:
1. 1-D Films;large displacement
2. Martensite/Martensite Films;large displacementlarge damping
NOVEL NiTi SHAPE MEMORY ALLOY FILMSManfred Wuttig
Manfred Wuttig Tel 301-405-5212 Fax 301-314-9467 Email [email protected]
COLLABORATORS
Kiyotaka MoriGrad. StudentPanasonic Res./Boston
Corneliu CraciunescuResearch Associate,U. Timisoara
Supported byOffice of Naval ResearchNational Science Foundation
NOVEL NiTi SHAPE MEMORY ALLOY FILMSManfred Wuttig
Manfred Wuttig Tel 301-405-5212 Fax 301-314-9467 Email [email protected]
Ehemaliger Dresdner,Anhänger des damaligen DSC: mehrmaliger Deutscher Meister, Heimat-mannschaft von Helmut Schön, des Trainers der Deutschen Fussballmannschaft.