Nickel -Titanium alloys (NiTi) PPT.pptx

Nickel-Titanium
Alloy
(Nitinol)
Presented by:
Shaima Mohammed
Malak Ayman
Buthainah Fuad
2023
Sana’a
Under supervision of:
Dr. Mohammed Gumaan
Dr. Hamdi Ghazi
UST

TABLE OF
CONTENTS
Introduction NiTi Alloys Ratio
and its Effects
Advantages and
Properties
Fabrication and
Treatment
Applications of
Nickel Titanium
01 02
04 05
03
06
Methods of
Testing

01 Introduction
• History
• Important terms

There are various types of materials
About 100 pure
elements 783 out of
possible 3,403
combinations of binary
alloys
about 2,000 to
5,000 types of
plastics, and
about 10,000
kinds of ceramics
334 out of 91,881
possible tertiary alloys
are considered as
practically usable metallic
materials
1.Introduction

CREDITS: This presentation template
was created by Slidesgo, including
icons by Flaticon, and infographics &
images by Freepik
1.Introduction
There are three major types of composites:
• Metal-matrix compounds
• Plastic-matrix compounds
• Ceramic-matric compounds.

It is common to classify materials into two
categories:
Functional materials
Structural materials
Structural materials are
nonactivatable materials that bear
load. The key properties of such
structural materials in relation to
bearing load are elastic modulus,
yield strength, ultimate tensile
strength, hardness, ductility,
fracture toughness, fatigue, and
creep resistance.
Functional materials are generally
characterized as those materials
which possess particular native
properties and function of their
own and can be used directly as
material-based energy converter;
in other words, it is possible to
modify their material properties
deliberately and reversibly.
1.Introduction

Functional materials examples
Piezoelectric
materials
ZnO, BaTiO3
Shape-memory
materials
Optomechanical
materials
LiNbO3, KTN
,ZnO
Electroactive
polymers
carbon
nanotubes
Optical
materials
SiO2, GaAs, glasses,
Al2O3, YAG
Magnetic
materials
Fe, Fe-Si, NiZn, MnZN
ferrites, γ-Fe2O3, Co-
Pt-Ta-Cr,
NiTi, ZrO2, AuCd, CuZnAl, polymer
gels, magnetorheological fluids
Energy technology and
environment
UO2, Ni–Cd,
ZrO2, LiCoO2
1.Introduction

History of NiTi
It was first discovered
in 1959 at the Naval
Ordinance Laboratory
where engineers were
challenged with
developing a nose cone
for the first submarine-
launched nuclear
ballistic missile.
1.Introduction
History of the discovery of shape-memory alloys

History of NiTi
Superelasticity
Biocompatibility and
safety of NiTi
1980s
2000
New powerful
actuators
1959
Discovery at Naval
Ordinance
Laboratory 1990s
1.Introduction

Important Terms
Shape memory alloys are a unique class of alloys that have
ability to ‘remember’ their shape and are able to return to that
shape even after being bent.
At a low temperature, a SMA can be seemingly plastically
deformed, but this ‘plastic’ strain can be recovered by
increasing the temperature. This is called the shape memory
effect (SME).
SMAs are classified as Smart Materials since they combine both
actuator and sensor functions with unique intrinsic properties
such as shape memory effect (SME) and superelasticity (SE)
1.Introduction

The unique properties of SMAs are controlled by and are
dependent on four external parameters:
Temperature (T) Stress (σ)
Time (t)
Strain (ε)
Shape memory alloys
1.Introduction

Important Terms
Nickel-Titanium:(NiTi) is the
most applied SMAs thin film
due to its high recoverable
strain and massive forces,
therefore, these high-
performance materials are
able to make microactuators
in Micro-Electro-Mechanical
System (MEMS).
1.Introduction
Nitinol:
Nickel Titanium alloy
discovered at the Naval
Ordinance Laboratory

Superelasticity (SE) refers to a
material that exhibits a reversible
austenitic-martensitic crystalline
structure in response to stress and
heat. It is also called
pseudoelasticity (PE)
Important Terms
Transformation temperature:
This is the temperature at which the phase changes
between austenite and martensite. Actually, the
temperature is a range and depends on whether
you are heating or cooling, so there is a martensite
start temperature (Ms), martensite finish
temperature (Mf), austenite start temperature (As),
and austenite finish temperature (Af).
1.Introduction

What is Austenite and martensite?
Austenitic structures are body-centered cubic.
martensitic structures are face-centered cubic.
1.Introduction
Important Terms

Primitive
(Or simple)
Body-centered Face-centered
Types of cell units
1.Introduction
Important Terms
The term “martensitic
transformation” can be defined
as a phase transformation within
a solid state, caused by shear
deformation without the long-
range diffusion (diffusionless)
transition of constituent atoms.
Martensitic phase transformation and its related phenomena.

The term martensite referring specifically
to the lower temperature phase, the term
austenite (or parent phase) referring to
the higher temperature phase from which
martensite (resulting from any athermal,
diffusionless phase transformation) is
formed. The martensitic transformation in
steel represents the most economically
significant example of this category of
phase transformations but with an
increasing number of alternatives with
SMAs taking into account.
1.Introduction
Important Terms
Martensitic phase transformation and its related phenomena:

Diffusional and Diffusionless transformation:
Diffusionless transformation
does not change the composition of the parent
phase, but rather only the crystal structure, so that it
does not require long-range atomic movement.
Transformations usually progress in a time-
independent fashion, with the speed of the interface
between the two phases able to move at nearly the
speed of sound. This type of transformation is
referred to as an athermal transformation since it
cannot progress at a constant temperature but
rather the amount of the new phase present
depends only upon temperature, not time.
are often referred to as
iso-thermal since they can
progress with time at a
constant temperature.
The diffusional
transformation takes place
with no change in phase
composition or number of
phases present.
1.Introduction
Important Terms
Diffusional transformations

There are four characteristic
temperatures involved in both SME
and SE:
● AS (austenitic transformation
starting temperature).
● AF (austenitic transformation
finishing temperature).
● MS (martensitic transformation
starting temperature).
● MF (martensitic transformation
finishing temperature).
1.Introduction
Important Terms Martensitic phase transformation and its related phenomena.

The dual-phase microstructure of NiTi
consists of two phases:
• The austenite phase (A), stable in high-
energy levels with a body-centered
cubic structure having low strain
• The martensite phase (M), stable in
low-energy levels having
transformation strain.
Both SE and SME properties occur as
a result of the austenite to
martensitic transformation, which can
be induced by stress or temperature.
Important Terms
1.Introduction

Stress–strain–temperature diagram of NiTi alloy. Red-
colored loop indicates SME phenomenon, blue-colored loop
represents SE phenomenon, and the black line shows an
ordinal stress–strain curve.
MF: martensite finish temperature
upon cooling
AS: temperature at which the
martensite (or R-phase) to austenite
transformation begins upon heating
AF :same completed transformation
MD: (martensite deformation
temperature) refers to the highest
temperature at which martensite will
form from austenite phase in
response to an applied stress; hence,
MD indicates the upper limit
temperature at which austenite is
subjected to stress-induced
martensitic transformation)
1.Introduction
Important Terms

In the stress–strain–temperature
diagram, there are three distinct zones:
 T < MS: stable martensite being
responsible to thermal memory
effect;
 MD< T <MS: metastable austenite
being responsible to mechanical
memory effect (or SE); and
 T > MD: stable austenite showing no
related effects
1.Introduction
Important Terms
MS: temperature at which martensitic transformation starts,
although it is not clearly determined) can be found in MF < MS < AS.
A: the austenite phase. M: the martensite phase. DM: deformed
martensite. TM: the twinned martensite (TM).

During the phase transformation between B2
phase (A: austenite) and B19′ (M: martensite)
phase, unique properties of shape-memory
effect (SME) and SE take place. For enhancing
these phenomena, normally postdeformation
annealing, thermal/mechanical cycling, aging,
and others are applied on NiTi materials.
Important Terms
1.Introduction
The austenite and martensite phases:

1.Introduction
Titanium
materials
flow
chart
involving
materials
sciences
and
engineering
disciplines

NiTi Alloys Ratio and its
Effects
• Effects of NiTi Ratio
• NiTi Ratio
• NiTi-X ternary alloys
02

NiTi is made of approximately equal amounts of nickel and titanium
(at atomic % level), and small variations in these proportions (in
other words, Ni/Ti ratio) have a radical effect on the properties of
the alloy in particular:
Its transformation
temperature
Physical and
mechanical
properties
Electrochemical
behavior
Chemical
behavior
Metallurgical
characteristics
02
01 03 04 05
2. NiTi Alloys Ratio and its Effects

The transformation from low-
temperature martensitic phase (M-
phase) to the high temperature parent
phase took place below room
temperature in Ni-rich NiTi while it
occurred above room temperature in
Ti-rich and near-equiatomic NiTi.

NiTi Ratio
Ni-rich NiTi
T-rich NiTi alloys.
01
02
0
3
near- or
equiatomic NiTi
Equiatomic NiTi (50
atomic% Ni, 50
atomic% Ti)

Partial phase diagram of NiTi system is given in
Figure. If nickel content is higher than 50.5 atomic%,
then the alloy will decompose during cooling below
973 K to TiNi and TiNi3. Nickel-rich (at 54–56 %. Ni)
NiTi-based alloys have gained increased attention for
their high hardness, corrosion resistance, strength,
and wear resistance, leading to their development
for high-performance bearings and other wear
applications

NiTi-X ternary alloys
• control transformation
temperatures
• reduce or increase
martensitic strength
• control the hysteresis
width
• increase the austenitic
strength
• increase two-way
effect ability
• increase the stability of MS with
respect to thermal history
The addition of the third or fourth alloying elements to NiTi-based
alloys is done for the following purposes :
• improve corrosion
resistance
• suppress the R-phase

NiTi-X ternary alloys
It was shown that, when the transition elements are
added to NiTi alloy:
The groups of V, Cr, Mn, Fe, Co, Pd, Cu
prefer the Ni sites; Sc, Y, Zr, Hf prefer the Ti
sites; Zn and Cd cannot form a stable
structure.
Substitution of Hf, Zr, Ag, Au for Ni and
substitution of Sc, Y, Hf, Zr for Ti will
increase the transformation temperature
Ms
The replacement of Ni by the groups of V, Cr,
Mn, Fe, Co or by Pd, Pt and the replacement of Ti
by V, Cr, Mn, Fe will lower the transformation
temperature Ms.
The transformation temperature will be
almost unchanged when Cu substitutes
for Ni

Advantages and
Properties
• Chemical Structure
• Advantages and
Disadvantages
• properties
03

•Chemical Structure
Chemical Structure Depiction. Source: Nickel titanium | NiTi - PubChem (nih.gov)
3. Advantages and Properties

Advantages and Disadvantages
Disadvantages
Advantages
• Low energy efficiency
• Complex thermo-mechanical
behavior
• Complex motion control
• Expensive materials
• Temperature dependent effect
• Poor fatigue properties
• Low operational speed
• High mechanical performances
• High power to weight ratio
• Large deformation
• Large actuation force
• High damping capacity
• High frequency response
• High wear resistance
• High corrosion and chemical resistance
• Low operation voltage
• compactness and lightness
• High specific strength

Properties
nickel-titanium,
shape-memory
nitinol, NiTi, Ni-Ti
Other
Names
52013-44-2
CAS No
Ni-Ti
Compound
Formula
N/A
Molecular
Weight
Appearance
black powder

Properties
1300°C
Melting
Point
N/A
Boiling
Point
6.45g/cm3
Density
N/A
Solubility
in H2O
Exact
Mass
N/A

04
Fabrication and
Treatment
• Heat treatment of
NiTi alloys
• Fabrication of NiTi
alloy

Heat treatment of NiTi alloys
Annealing at temperature higher
than 800 °C, formed and treatment
at relatively low temperature ranging
from 200 to 300 °C.
Hardening by a cold working,
followed by medium-temperature
treatment at a range from 400 to
500 °C for 1 h”
“Saturn is the ringed
one and a gas giant”
Solution treatment followed by aging at 400 °C for several hours. Hence,
heat treatments are diverse and appropriate selection and proper practice,
thereof, should become a very crucial issue to make either/ both shape-
memory effect (SME) and superelasticity (SE) phenomena into more
efficient and efficacious manner.
There are three ways to memorize (train) the shape of (potentially shape
recoverable) NiTi alloy:
4. Fabrication and Treatment

Various routes are used to fabricate NiTi products
Fabrication of NiTi alloy

Additive
Manufacturing
conventional
methods
Casting
powder
metallurgy
powder-bed flow-based
Methods

Casting technique: This technique is associated with high temperature melting
procedures that result in an increase in the impurity level (e.g., carbon, oxygen),
and, therefore, the formation of Ti-rich phases.
Powder metallurgy: It is used for producing near-netshape devices. Powder
preparation is a required step prior to PM processing.
Additive Manufacturing (AM) has gained significant attention for processing NiTi
because they have circumvented many of the challenges associated with the
conventional methods.

Additive Manufacturing:
The first step in AM processing is preparing the NiTi powder. The ratio of Ni and
Ti elements are important factors to guarantee the desired functional properties
(i.e., shape memory or superelasticity) of the final part.
The second important requirement for the AM processing is the processing
parameters. Optimal parameters are methodically developed to make sure that
the final product is not only fully dense, but also shows a low level of impurity
contents.
The third important requirement is to provide an inert atmosphere (e.g., argon)
throughout the processing to minimize the oxidation and impurity pick-up (e.g.,
oxygen and carbon), increase the surface quality, enhance the density and,
achieve similar functional behavior to the conventionally processed NiTi.

powder-bed
based
technologies,
such as selective
laser sintering
(SLS), direct
metal sintering
(DMLS), selective
laser melting
(SLM), and
LaserCUSING.
The sequence of operation of powder-bed based machines. This procedure
starts with slicing the CAD model, and continues with a repeatable three-step
procedure. After the supports and loose powders are removed, the final
product is ready to use.

Schematic representation of
flow-based methods. This
procedure initiates with slicing
the CAD model and continues
with depositing and laser
scanning the powder
simultaneously. After the
completion of each layer, the
nozzle and lens move up by a
thickness layer to allow the
fabrication of the next layer

Applications of
Nickel Titanium
05 • General application of Nickel
Titanium alloys includes
• Application of Nickel Titanium alloys
as biomaterial

1
5.Applications of Nickel Titanium
General applications of Nickel Titanium
In a heat engine, fluid is first heated, which then
flows through a radiator to produce power.
Nickel-titanium alloys are used here because
they have high thermal conductivity and can be
used at high temperatures. Nickel-titanium alloy
typically has thermal conductivity ranging
between 5.6 to 7.1 W/mK at temperatures above
1,000 degrees Celsius (1832 degrees
Fahrenheit), making them perfect for heat
In Heat
Engines

5.Applications of
Nickel Titanium
• Nitinol can be used to replace traditional actuators (solenoids,
servo motors, etc.).
• Nitinol springs are used for fluid thermal valves, in which the material can
be used as both a temperature sensor and an actuator.
• It is used as an autofocus actuator in motion cameras and an optical
image stabilizer in mobile phones.
• It is used in pneumatic valves for comfortable seats and has become the
industry standard.
• 2014 Chevrolet Corvette uses Nitinol actuators to open and close hatch
vents that release air from the trunk, making them easier to close, instead
of heavier electric actuators. Nitinol can be used to replace traditional
actuators (solenoids, servo motors, etc.)
Thermal and
electrical
actuators
2

5.Applications of
Nickel Titanium
This alloy is also used in retractable antennas and
boom microphones because it has a very low
coefficient of friction and can withstand high loads.
Plus, nickel-titanium alloy is very strong and durable
because of its ability to withstand high pressure and
extreme temperatures, making it perfect for any
scenario that requires durable equipment.
Retractable
Antennas
3

5.Applications of
Nickel Titanium
The alloy is used in the manufacturing of resilient glass frames
that are able to withstand high-impact forces. Modern glasses
require frames that bend or move with the impact to prevent
permanent damages. Thus, nickel-titanium alloys are used in
the creation of frames because of their superelasticity, making
them highly resistant to breaking.
Thus, this alloy is a fundamental part of many major industries,
and its applications continue to increase, making it a reliable
material for a plethora of manufacturers.
Resilient Glass
Frames
4

5.Applications of
Nickel Titanium
NASA has developed a new ball bearing material, Nickel
Titanium-Hafnium (NiTi-Hf), to replace 60NiTi in many flight
applications. A new NiTi alloy containing 1 atomic percent
(~3.9% by weight) Hf, designated NiTi-Hf, has been shown
to achieve high hardness even without resorting to a rapid
water quench heat treatment. Further, the Hf addition
works as a trap for trace amounts of oxygen yielding finer
and more homogenous microstruc-tures with better rolling
contact fatigue behavior than the baseline 60NiTi alloy.
Ball Bearings
5
General applications of Nickel
Titanium
The addition of a small amount of
Hf to the baseline 60NiTi alloy
(top) gives a more homogenous
and fracture resistant
microstructure (bottom) in the
newly developed NiTi-Hf

5.Applications of
Nickel Titanium
Applications of Nickel Titanium
Recently, new flight bearings made with the NiTi-Hf alloy have
been produced and have passed long-term 5000-hour ground
tests, a prerequisite for flight use (Figure 5.1). Based on the
benefits to performance and processability afforded by the
new composition, NASA plans to phase out the use of 60NiTi in
favor of NiTi-Hf. Work is also underway to extend the materials
and processing specification for 60NiTi (MSFC-SPEC-3706) to
encompass the new alloy. The rapid progress achieved has
greatly aided the commercialization of the technology, which
is already available from at least two major bearing companies.
Ball Bearings
5

Application of Nickel Titanium alloys as
biomaterial
Biomaterials are those materials that are used in the human body.
Biomaterials should have two important properties:
biofunctionality and biocompatibility. Good biofunctionality means
that the biomaterial can perform the required function when it is
used as a biomaterial. Biocompatibility means that the material
should not be toxic within the body. Because of these two rigorous
properties required for the material to be used as a biomaterial,
not all materials are suitable for biomedical applications. The NiTi
alloys have been investigated extensively for 30 years after the
establishment of basic understanding on the relationship among
the microstructure, transformation behavior, and SME/SE
phenomena. Many applications have been successfully developed
in both engineering and medical fields 5.Applications of
Nickel Titanium

Application of Nickel Titanium alloys as
biomaterial
Biomedical applications of nitinol are related to
transformation temperatures of nitinol that are close to body
temperature (310K). Due to thermoelastic martensitic phase
transformation and reverse transformation to parent
austenite upon heating (shape memory effect) or upon
unloading (superelasticity), nitinol has a large number of
biomedical applications. Another important property of
nitinol is its low elastic modulus close to natural bone
material and compressive strength higher than natural

Medical applications for nitinol include
In colorectal surgery,
the material is used
in various devices
for reconnecting the
intestine after a
pathology is
removed.
01
03
02
Dentistry, especially
in orthodontics for
wires and brackets
that connect the
teeth. “Sure Smile”
dental braces are an
example of its
application in
orthodontics.
Endodontics,
mainly during
root canals for
cleaning and
shaping root
canals

•Mechanical actuation to
fight muscle atrophy (in
research at Har-vard)
•Dissolvable devices (in
research at MIT)
04
06
05
Stents and stent
retrievers, such as the
Johnson & Johnson Em-
botrap device for
removing blood clots
(thrombectomy) in
ischemic stroke
patients
•Orthopedic implants
•Wires for marking and locating
breast tumors
•Tubing for a range of medical
applications
•Ablation catheter tips

Similarly, foldable
structures consisting of
braided microscopic fine
Nitinol filaments can be
used for neurovascular
interventions such as
stroke thrombolysis,
embolization, and
intracranial angioplasty.
07 09
08
Nitinol was used in a
device developed by
Franz Freudenthal to
treat patent ductus
arteriosus, a blockage in
a blood vessel that
bypasses the lungs and
fails to close after birth.
•Synchron’s catheter-
placed Stentrode brain-
control-interface im-plant.
•In colorectal surgery, the
material is used in a device
to rewire the intestine
after removing pathogens.

10
Recently nitinol wire is
used in female
contraception, particularly
in intrauterine devices

[1] Yoshiki, O., & Toshihiko, T. (2020). NiTi Materials: Biomedical Applications. by the Deutsche
Nationalbibliothek.
[2] https://www.sciencedirect.com/book/9780857091291/mems-for-biomedical-applications
[3] Mehrpouya, M., & Bidsorkhi, H. C. (2016). MEMS applications of NiTi based shape memory alloys: A
review. Micro and Nanosystems, 14.
https://www.researchgate.net/figure/Advantages-and-disadvantages-of-NiTi-SMA_tbl1_311202728
[4] https://www.cdn-inc.com/nitinol/
[5] Effect of Ni/Ti Ratio and Ta Content on NiTiTa Alloys | SpringerLink
[6] Development of Nickel-Rich Nickel–Titanium–Hafnium Alloys for Tribological Applications | SpringerLink
[7] https://customwiretech.com/2021/07/the-nitinol-advantage/
[8] What Are Shape Memory Alloys? (Metallurgy, How They Work, and Applications) – Materials Science &
Engineering (msestudent.com)
Resources

[9] Volume 2016 | Article ID 4173138 | Brief Overview on Nitinol as BiomaterialAbdul Wadood Brief
Overview on Nitinol as Biomaterial (hindawi.com)
[10] 4 Uses of Nickel-Titanium Alloy (alnorindustries.com)
[11] NiTi-Hf Alloy for Corrosion Immune, Shockproof Bearings | NASA
[12] Properties and Applications of Nickel-Titanium Alloy (nanotrun.com)
[13] What is nitinol and where is it used? (medicaldesignandoutsourcing.com)
[14] Fabrication of NiTi through Additive Manufacturing: A Review
https://www.sciencedirect.com/science/article/pii/S0079642516300469
[15] Marchenko, E.; Baigonakova, G.; Dubovikov, K.; Kokorev, O.; Yasenchuk, Y.; Vorozhtsov, A. In Vitro Bio-
Testing Comparative Analysis of NiTi Porous Alloys Modified by Heat Treatment. Metals 2022, 12, 1006
https://doi.org/10.3390/met12061006
Resources

CREDITS: This presentation template
was created by Slidesgo, including
icons by Flaticon, and infographics &
images by Freepik
Do you have any
questions?
THANKS

Nickel -Titanium alloys (NiTi) PPT.pptx

Recommended

Recommended

More Related Content

What's hot

What's hot (20)

Similar to Nickel -Titanium alloys (NiTi) PPT.pptx

Similar to Nickel -Titanium alloys (NiTi) PPT.pptx (20)

Recently uploaded

Recently uploaded (20)

Nickel -Titanium alloys (NiTi) PPT.pptx