Shape memory alloy (ni tinol)

Under the guidance of:DR. I.A. PalaniDr. C.p. Paul

Presented by:Sandesh Dhurve

Nishchay Sharma

I.i.t. Indore R.r.c.a.t. indore

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contentsResearch Objective

• Project Title

• Overview

Introduction to Shape Memory Alloy

• Nitinol

Rapid Manufacturing using Lasers

• Experimental setup

• Obtained results

Spring & Parallel Manipulator

• CAD model

• Analysis using ANSYS

References

2

Rapid Manufacturing of Nitinol using Lasers

• Deposition of Ni-Ti powder on Ti plate using High power Laser deposition

• Manufacturing of a leaf spring

Parallel Manipulator with SMA springs

• CAD modeling of the parallel manipulator

• Modeling of helical and leaf springs

Analysis using ANSYS

• Analyzing the behavior of SMA springs with respect to temperature

• Study of the actuation mechanism of SMA springs in 3-DOF parallel manipulator

Research Objective

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Shape Memory Alloy It remembers its shape

Deformed shape + Heat = Original shape

The high temperature causes the atoms to

arrange themselves into the most compact

and regular pattern possible

Example: Copper-Aluminum-Nickel,

Copper-Zinc-Aluminum,

Iron- Manganese-Silicon and

Nickel-Titanium alloys

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APPLICATIONS SMA have applications in industries like-

Medical: Mending bones, Stent in artries, Eyeglass frames, Tooth clips

Safety: Anti-scalding devices and fire sprinklers

Military: Nitinol couplers in F-14 fighter planes

Robotics: As an actuator5

NITINOL (Ni-Ti) Was discovered in Naval Ordnance

Laboratory (NOL), Maryland, USA

Ni- 50% , Ti- 50%

0

10

20

30

40

50

60

70

80

290 310 330 350 370 390 410

Yo

un

g's

Mo

du

lus (

GP

a)

Temperature (K)

Young's Modulus v/s Temp

Temperature (K)

Young's Modulus (GPa)

294.25 27.17299.85 24.82305.35 22.41310.95 20.06316.45 25.72322.05 31.37327.55 36.96333.15 42.61338.75 48.27344.25 54.88349.85 61.43355.35 64.19360.95 63.16366.45 62.06372.05 63.92377.55 65.78383.15 67.64388.75 69.5394.25 71.36399.85 70.81405.35 70.33410.95 69.78416.45 69.29

FACT: Even 0.l wt% variation of composition

causes 10 K error of transformation temperature.

HIGHLY SENSETIVE TO COMPOSITION!!6

SME in NiTinolBy change in phase from

Martensite to Austenite

Monoclinic FCC (Martensite) to BCC (Austenite)

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ADVANTAGES Compactness, allowing for reduction in overall actuator size.

Very high power/weight ratio comparatively

Accessible voltages can accomplish thermo elastic transformation

Higher strain recovery

Higher strength

Noiseless and silent operation

High corrosion resistance

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LIMITATIONS Heat Dissipation, need Mechanism for cooling

Less Stiffness / high Flexibility

Relatively expensive to manufacture and machine

compared to other materials such as steel and

aluminum.

Most SMA's have poor fatigue properties ( a steel

component may survive for more than one hundred

time more cycles than an SMA element. )

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Rapid manufacturing using lasers

(LRM)

FABRICATION OF PARTS

CAD Model Powder Material

EXTENSION OF LASER CLADDING PROCESS

Deposition of a metal on another

Metallurgical bonds are formed

STEP TOWARDS FEATURE BASED DESIGN & MANUFACTURING

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Experimental setupSchematic diagram:

Ni + Ti powder

Ni

Ni TiPowder

Feeder

CNC

• High power Laser

• 5 axes manipulator with CNC control

• Argon atmosphere (965 mbar)

• No moisture!!

Closed

loop

process

controlGuide Laser

• Marking the trajectory

• ƛ=605nm

• Red color laser

Nozzle

• Laser nozzle dia.= 3.29mm

• Powder feed nozzle dia.=1.96mm

Deposition

• Melting of powder by power laser

(IR) ƛ=1080nm

• Power of laser= 700W

Deposition mechanism

of Ni-Ti powder on Ti

plate 11

POWER LASER SPECIFICATIONS

ƛ=1080nm (IR laser); feed= 4gm/min

Ytterbium laser system YLS-2000

A coolant is used for cooling the nozzle.

Temperature of nozzle is kept around 21-22 C

Maximum power of the laser= 2000W

Power during process= 700W

LRM based CNC Machine

Power of the laser is adjusted to get

proper penetration, melting and

deposition. Less power causes poor

melting and high power causes

sputtering!! 12

Modeling & Simulation Helical spring

Diameter of spring…………………..D = 1.5mm

Wire diameter………………………..d = 0.5 mm

Number of turns……………………..n = 40

Length of fully compressed spring….L= 20 mm

Leaf spring

Rectangular cross section…………..w = 5mm

h = 5mm

Arc radius…………………………..r = 37.5 mm

Parallel manipulator with helical spring

Parallel manipulator with leaf spring

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Spring simulation.avi

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Temp (C) Deflection (mm) Force (N) Deflection (mm) Force (N) Temp (C) Deflection (mm)

25 0.0054 0.1 10.4130 0.1 25 10.9300

35 0.0235 0.2 20.8260 0.1 35 13.1570

45 0.0416 0.3 31.2380 0.1 45 10.2030

55 0.0597 0.4 41.6510 0.1 55 7.4750

65 0.0774 0.5 52.0640 0.1 65 5.9168

75 0.0958 0.6 62.4770 0.1 75 4.7720

85 0.1139 0.7 72.8890 0.1 85 4.4750

95 0.1320 0.8 83.3020 0.1 95 4.5630

105 0.1501 0.9 93.7150 0.1 105 4.3518

115 0.1681 1 104.1300 0.1 115 4.1642

125 0.1862 0.1 125 4.0842

Force suppressed,

Variable temperature

Temperature suppressed ,

Variable force

Force and Temperature both

acting

Result for helical spring

0.0000

2.0000

4.0000

6.0000

8.0000

10.0000

12.0000

14.0000

5 15 25 35 45 55 65 75 85 95 105 115 125 135

Def

lect

ion

(mm

)

Temperature (C)

Force and Temperature both acting

15

16

Temp (C) Deflection (mm) Force (N) Deflection (mm) Force (N) Temp (C) Deflection (mm)

25 0.0093 10 6.0999 10 25 6.4027

35 0.0403 11 6.7099 10 35 7.7051

45 0.0713 12 7.3199 10 45 5.9729

55 0.1024 13 7.9299 10 55 4.3740

65 0.1335 14 8.5398 10 65 3.4603

75 0.1645 15 9.1498 10 75 2.7898

85 0.1955 16 9.7598 10 85 2.6161

95 0.2265 17 10.3700 10 95 2.6681

105 0.2576 18 10.9800 10 105 2.5454

115 0.2886 19 11.5900 10 115 2.4373

125 0.3197 20 12.2000 10 125 2.3925

Force suppressed,

Variable temperature

Temperature suppressed ,

Variable force

Force and Temperature both

acting

Result for Leaf spring

0.0000

1.0000

2.0000

3.0000

4.0000

5.0000

6.0000

7.0000

8.0000

9.0000

5 15 25 35 45 55 65 75 85 95 105 115 125 135

Def

lect

ion

(mm

)

Temperature (C)

Force and Temperatrue both acting

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parallel

manupulatorsimulation.avi

18

Force (N) Temp ( C ) Total Spring 1 Spring 2 Spring 3

0.05 Environmental 20.2930 10.522 10.7260 16.3430

0.05 35 22.2210 11.093 12.2990 17.8990

0.05 45 20.1280 10.465 10.6050 16.2100

0.05 55 17.7010 9.6972 8.9032 14.2510

0.05 65 15.9280 9.0501 7.8294 12.8190

0.05 75 14.3210 8.3799 6.9504 11.5160

0.05 85 13.8350 8.1568 6.6986 11.1240

0.05 95 13.9650 8.2092 6.7682 11.2290

0.05 105 13.6010 8.0367 6.5820 10.9350

0.05 115 13.2620 7.874 6.4107 10.6610

0.05 125 13.1030 7.7921 6.3321 10.5330

Result for Parallel manipulator with

helical spring

Deflection (mm)

0.0

5.0

10.0

15.0

20.0

25.0

5 15 25 35 45 55 65 75 85 95 105 115 125 135

Def

lect

ion

(mm

)

Temperature (C)

Total

Spring 1

Spring 2

Spring 3

19

20

Force (N) Temperature ( C ) Total Leaf 1 Leaf 2 Leaf 3

1000 25 1.8658 1.8658 1.1747 1.1969

1000 35 1.9659 1.9659 1.2291 1.2529

1000 45 1.8510 1.8510 1.1612 1.1831

1000 55 1.6976 1.6976 1.0702 1.0903

1000 65 1.5812 1.5812 0.9993 1.0185

1000 75 1.4751 1.4751 0.9334 0.9520

1000 85 1.4547 1.4547 0.9178 0.9362

1000 95 1.4811 1.4811 0.9304 0.9487

1000 105 1.4709 1.4709 0.9209 0.9390

1000 115 1.4632 1.4632 0.9127 0.9306

1000 125 1.4691 1.4691 0.9128 0.9306

Deflection (mm)

Result for parallel manipulator with Leaf Springs

0.0000

0.5000

1.0000

1.5000

2.0000

2.5000

5 15 25 35 45 55 65 75 85 95 105 115 125 135

Def

lect

ion

(mm

)

Temperature (C)

Total

Leaf 1

Leaf 2

Leaf 3

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REFERENCES

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http://www.stanford.edu/~richlin1/sma/sma.html

www.wikipedia.org

Peter R. Barrett, Daniel Fridline. “User Implemented Nitinol

Material Model in ANSYS”.

Kaan Divringi & Can Ozcan. “Advanced Shape memory alloy

material models for ANSYS”. Ozen Engineering Inc.

Eiji makino, Takashi Mitsuya, Takayuki Shibata. “ Fabrication

of TiNi shape memory actuator for micropump”. Proc. SPIE

3891, Electronics and Structures for MEMS, 328 (September

29, 1999); doi:10.1117/12.364458

Shape Memory Alloy, BTP Report by Saurabh Maghade and

Sahil Agarwal.

THANK YOU!!

ANY QUESTIONS??

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