SHAPE MEMORY ALLOY

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

Presented by:Sandesh DhurveNishchay Sharma

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

1

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

3

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

4

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%

290 310 330 350 370 390 4100

10

20

30

40

50

60

70

80

Young's Modulus v/s Temp

Temperature (K)

Young's

Modulu

s (

GP

a)

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 NiTinol By change in phase from Martensite to Austenite

Monoclinic FCC (Martensite) to BCC (Austenite)

7

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

8

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. )

9

Rapid manufacturing using lasers (LRM)

FABRICATION OF PARTS

CAD Model Powder Material

EXTENSION OF LASER CLADDING PROCESSDeposition of a metal on

anotherMetallurgical bonds are

formed

STEP TOWARDS FEATURE BASED DESIGN & MANUFACTURING

10

Experimental setupSchematic diagram:

Ni + Ti powder

NiNi Ti

Powder Feeder

CNC• High power Laser• 5 axes manipulator

with CNC control• Argon atmosphere

(965 mbar)• No moisture!!

Closed loop

process control

Guide 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

13

14

Spring simulation.avi

Temp (C) Deflection (mm) Force (N) Deflection (mm) Force (N) Temp (C) Deflection (mm)25 0.0054 0.1 10.4130 0.1 25 10.930035 0.0235 0.2 20.8260 0.1 35 13.157045 0.0416 0.3 31.2380 0.1 45 10.203055 0.0597 0.4 41.6510 0.1 55 7.475065 0.0774 0.5 52.0640 0.1 65 5.916875 0.0958 0.6 62.4770 0.1 75 4.772085 0.1139 0.7 72.8890 0.1 85 4.475095 0.1320 0.8 83.3020 0.1 95 4.5630

105 0.1501 0.9 93.7150 0.1 105 4.3518115 0.1681 1 104.1300 0.1 115 4.1642125 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

Defl

ecti

on (m

m)

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 6.402735 0.0403 11 6.7099 10 35 7.705145 0.0713 12 7.3199 10 45 5.972955 0.1024 13 7.9299 10 55 4.374065 0.1335 14 8.5398 10 65 3.460375 0.1645 15 9.1498 10 75 2.789885 0.1955 16 9.7598 10 85 2.616195 0.2265 17 10.3700 10 95 2.6681105 0.2576 18 10.9800 10 105 2.5454115 0.2886 19 11.5900 10 115 2.4373125 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

0.00001.00002.00003.00004.00005.00006.00007.00008.00009.0000

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

Defl

ecti

on (

mm

)

Temperature (C)

Force and Temperatrue both acting

17

18

parallel manupulatorsimulation.avi

Force (N) Temp ( C ) Total Spring 1 Spring 2 Spring 30.05 Environmental 20.2930 10.522 10.7260 16.34300.05 35 22.2210 11.093 12.2990 17.89900.05 45 20.1280 10.465 10.6050 16.21000.05 55 17.7010 9.6972 8.9032 14.25100.05 65 15.9280 9.0501 7.8294 12.81900.05 75 14.3210 8.3799 6.9504 11.51600.05 85 13.8350 8.1568 6.6986 11.12400.05 95 13.9650 8.2092 6.7682 11.22900.05 105 13.6010 8.0367 6.5820 10.93500.05 115 13.2620 7.874 6.4107 10.66100.05 125 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

Defl

ecti

on (

mm

)

Temperature (C)

Total

Spring 1

Spring 2

Spring 3

19

20

Force (N) Temperature ( C ) Total Leaf 1 Leaf 2 Leaf 31000 25 1.8658 1.8658 1.1747 1.19691000 35 1.9659 1.9659 1.2291 1.25291000 45 1.8510 1.8510 1.1612 1.18311000 55 1.6976 1.6976 1.0702 1.09031000 65 1.5812 1.5812 0.9993 1.01851000 75 1.4751 1.4751 0.9334 0.95201000 85 1.4547 1.4547 0.9178 0.93621000 95 1.4811 1.4811 0.9304 0.94871000 105 1.4709 1.4709 0.9209 0.93901000 115 1.4632 1.4632 0.9127 0.93061000 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

Defl

ectio

n (m

m)

Temperature (C)

Total

Leaf 1

Leaf 2

Leaf 3

21

22

REFERENCES 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.

23

THANK YOU!!

ANY QUESTIONS

??