Characterization Techniques of NiTi Shape Memory Alloys

Francisco M. Braz FernandesFrancisco M. Braz Fernandes0 1 2 3 4 5 6 7 8 9

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Ni-rich NiTidia=1mm GL=57.8mm; CycTest upto 5.112mm(@9%)A=0.5A(0.13V)2nd cycle

Ele

ctric

al R

esis

tivity

( μΩ

-cm

)

Strain, ε (%)

Strain, ε

Strain, ε

Stre

ss, σ

(MPa

)

Stre

ss, σ

Stre

ss, σ

Below Mf

Temperature, T

Critical stress for dislocation slip (A)

Super-elasticity

Shape memoryeffect

Shape memory effect versus superelasticity

Critica

l stre

ss fo

r stre

ss in

duce

d mar

tensit

e

Critical stress for dislocation slip (B)

Above Af

NiNi--TiTi SystemSystem

Ligasricas em Ti

Ligasricas em Ni

W. Tang, B. Sundman, R. Sandström, C. Qiu. Acta materialia 47 (1999) 3457-3468

Austenite(B2)

Cubic

Martensite(B19’)

Monoclinic

R-phase(R)

Rhombohedral

DilatometryElectrical Resistivity

Transformation Characteristics

Cooling

Heating

Cooling

Heating

Cooling

Heating

DSC

Base Material Heat Affected ZoneHeat Affected ZoneWeld BeadWeld Bead

2 Theta

Martensite

Austenite

Martensite

TwoTwo magnetronsmagnetrons (1(1--inch inch diameterdiameter)) with shutterswith shutters

Entrance window for the Entrance window for the incoming beamincoming beam

Exit window for the Exit window for the diffracted beamdiffracted beam

Substrates carrier with Substrates carrier with heaterheater and and bias voltagebias voltage Tube to the z drive Tube to the z drive

Window protection foilsWindow protection foils

SpecificationsSpecifications• 2 unbalanced magnetrons with variable ion flux and energy (gas pressure, biasvoltage)• substrate heater (deposition at various

temperatures / annealing up to 700oC) • additional 2 gas supplies and 1 viewport

60o rotation

start

1st scan

+

background

20 W Ti

-10o rotation

B2 ⎨110⎬

Ti2Ni

90o rotation

B2(110)

Ti2Ni

20 W Ti0 W Ti0 W Ti

40 W TiNi + co-sputtering

30 W Ti

no sputtering

targets NiTi 40 W + co-sputtering Ti

Ar 3.5 E-3 mbarTdep = 450oC

Real-time in-situ phase design of NiTi SMA

Sample 6

B2(200)

Ti2Ni(511) B2(110)

Ti2Ni(440)

0 20 40 60 80 100 120 140 160 1800

100

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500

Time (min.)

Net A

rea

(arb

. uni

ts)

Net area: B2(110) : B2(200)

Δa0

: B2(110) : B2(200)

3.02

3.03

3.04

3.05

3.06

3.07

3.08

Lattice parameter, a

0 (Å)

InIn situsitu XRD XRD studystudy ofofrecrystallization recrystallization ofof NiTiNiTi

“Study of the textural evolution in Ti-rich NiTi using synchrotron radiation”.A.S. Paula, J.H.P.G. Canejo, K.K. Mahesh, R.J.C. Silva, F.M. Braz Fernandes, R.M.S. Martins, A.M.A. Cardoso, N. Schell. Nuclear Instruments & Methods Physics B 246 (2006) pp. 206-210

ElectricalElectrical resistivityresistivityduringduring tensiletensile testingtesting

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Strain (%)

Stre

ss (M

Pa)

Nor

mal

ised

Res

ista

nce

1,0

1,2

1,4

1,6

1,8

2,0

2,2

(i) Identification step

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Stre

ss (M

Pa)

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ised

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2,0

2,2

(i) Identification step0 2 4 6 8 10

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ss (M

Pa)

Strain (%)

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isita

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(i) Identification step

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Strain (%)

Stre

ss (M

Pa)

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mal

ised

Res

ista

nce

(iii) Eraser step

1.0

1.2

1.4

1.6

1.8

2.0

2.2

0 2 4 6 8 10

0

100

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400

500

600

Stre

ss (M

Pa)

Strain (%)

(ii) 3 Sub-cycles followed by a complete cycle

“Micromemory effects involved during martensitic transformation in Ni-rich NiTi alloys”.K. Mahesh, F. M. Braz Fernandes, C. M. L. Santos. Materials Science Forum 514-516 (2006) pp. 1668-1672.

ElectricalElectrical resistivityresistivityduringduring tensiletensile testingtesting

0.1565

0.1570

0.1575

0.1580

0.1585

0.1590

0.1595

0.1600

0.1605

3765 3785 3805 3825 3845 3865 3885 3905

Time (sec)

Res

ista

nce

/ Str

ain

(a.u

.)

res(V)strain

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s (M

Pa)

Strain (%)

Ni-rich NiTidia=1mm GL=57.8mm; CycTest upto 5.112mm(@9%)A=0.5A(0.13V)2nd cycle

Ele

ctric

al R

esis

tivity

(μΩ

-cm

)

0.1565

0.1570

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3765 3785 3805 3825 3845 3865 3885 3905

Time (sec)

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ista

nce

/ Str

ain

(a.u

.)

res(V)strain

InIn situsitu XRD / ERXRD / ER

25 26 27 28 29 30 31 32 33 34

100

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7055

-10

-30-40

-20

B19

'(1 1

1)

B19

'(0 0

2)

R(3

0 0

)B

2(1

1 0)

R(1

1 2

)

B19'

(1 1

1)

B19

'(0 2

0)

B19'

(1 0

1)

Dec

reas

ing T

empe

ratu

re (º

C)

2 Theta

Inte

nsity

(Log

Cou

nts)R

(1 0

2)

-50

-50 -40 -30 -20 -10 0 10 20 30 40 50 60 701

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Inte

grat

ed A

rea

(log

scal

e)

Temperature (ºC)

(a) B2(1 1 0) R(1 1 2) R(3 0 0) R(1 0 2) Bulk ER

Bul

k E

R (μ

Ω-c

m)

-50 -40 -30 -20 -10 0 10 20 30 40 50 60 7010

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B19'(1 0 1) B19'(0 2 0) B19'(1 1 1) B19'(0 0 2) B19'(1 1 1)

Inte

grat

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rea

(log

scal

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(b)

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Bul

k E

R (μ

Ω-c

m)

Resistividade eléctrica / DRX in situ

R-phase

R-phaseR-phase

B2

B19’ B2

Heating

Cooling

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(log

scal

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(a) B2(1 1 0) R(1 1 2) R(3 0 0) R(1 0 2) Bulk ER

Bul

k E

R (μ

Ω-c

m)

-50 -40 -30 -20 -10 0 10 20 30 40 50 60 7010

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B19'(1 0 1) B19'(0 2 0) B19'(1 1 1) B19'(0 0 2) B19'(1 1 1)

Inte

grat

ed A

rea

(log

scal

e)

Temperature (ºC)

(b)

Bulk ER

Bul

k E

R (μ

Ω-c

m)

“Simultaneous probing of phase transformations in Ni-Ti thin film Shape Memory Alloy by synchrotron radiation-based X-ray diffraction and Electrical Resistivity”. F.M. Braz Fernandes, K.K. Mahesh, R.M.S. Martins, R.J.C. Silva, C. Baehtz, J. von Borany. Materials Characterization 76 (2013) pp. 35-38

EndodonticEndodontic filesfiles

“Mechanism of NiTi file fracture based on rotation/flexion assays in threeendodontic files”. S. Vilaverde Correia, R. J. C. Silva, M.T. Nogueira, R. F. Martins, L. Pires Lopes, F.M. Braz Fernandes. Actas de “11ª Jornadas Portuguesas de Fractura / 11th Portuguese Conference on Fracture” (ISBN 978-989-95683-0-3), pp 383- 392, Caparica, 2008.

EndodonticEndodonticfilesfiles

EndodonticEndodontic filesfilesM

-Tw

o .

04(3

5)

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le.0

4(3

5)

InIn situsitu XRD XRD ofof thermomechanicalthermomechanical cyclingcycling

InIn situsitu XRD XRD ofof thermalthermal / / mechanicalmechanical

cyclingcyclingThermal cycling

Stress inducedprecipitation

Multilayer reaction

AcknowledgementsAcknowledgements

A. A. CavaleiroCavaleiro (CEMUC), (CEMUC), A.S. Paula (CENIMAT, now with A.S. Paula (CENIMAT, now with UniversidadeUniversidade Federal Federal FluminenseFluminense –– UFF)UFF),,C. C. BaetzBaetz (ROBL (ROBL –– ESRF; HZDR),ESRF; HZDR),F. F. NevesNeves (CENIMAT, now with LNEG),(CENIMAT, now with LNEG),J.P. Oliveira (CENIMAT),J.P. Oliveira (CENIMAT),K.K. Mahesh (CENIMAT, now with K.K. Mahesh (CENIMAT, now with Vivekananda College of Engineering & Technology)Vivekananda College of Engineering & Technology), , M.T. M.T. NogueiraNogueira (CENIMAT),(CENIMAT),M.T. VieiraM.T. Vieira (CEMUC),(CEMUC),N. Schell (P07N. Schell (P07--PETRA, HZG), PETRA, HZG), R.J.C. Silva (CENIMAT),R.J.C. Silva (CENIMAT),R.M. Miranda (UNIDEMI),R.M. Miranda (UNIDEMI),R.M.S. Martins (CENIMAT, ITN),R.M.S. Martins (CENIMAT, ITN),S. Ramos (CEMUC),S. Ramos (CEMUC),S.V. S.V. CorreiaCorreia (CENIMAT),(CENIMAT),

Master thesis completed

• Rui Miguel Santos Martins, “Produção de películas finas de ligas Ni-Ti com memória de forma para aplicações em dispositivos microelectromecânicos”, FCT/UNL, 29/07/2004. Supervisor: F. M. Braz Fernandes.• João Paulo Heitor Godinho Canejo, “Tratamento térmico de ligas de memória de forma visando a obtenção de diferentes gamas de temperaturas de transformação”, FCT/UNL, 06/04/2005. Supervisor : F. M. Braz Fernandes.• Daniel Silva, “Modelação numérica de compósitos inteligentes” . FCT/UNL, 24/07/2008. Supervisors: Rui Martins (DEMI, FCT/UNL) e F. M. Braz Fernandes.• Ricardo Nascimento, “Produção e Caracterização de Compósitos Inteligentes”, FCT/UNL, 20/03/2009. Supervisors: F. M. Braz Fernandes e A. Velhinho.• Cátia Gaspar, “Aplicações de ligas NiTi em Engenharia Civil”, Univ Católica e FCT/UNL. Supervisors: F. M. Braz Fernandes e Ionut Moldovan (Univ Católica).• Diana Cardoso Simão. Mestrado Integrado em Medicina Dentária (UL). Caracterização térmica de limas System Profile GT e de limas ProFile GT series X em estado novo. Mestrado Integrado em Medicina Dentária (FMD-UL). Supervision: Sancho Correia (FMD-UL), F.M. Braz Fernandes.• Francisca Neves Sena Alçada Ribeiro. Mestrado Integrado em Medicina Dentária (UL). Caracterização de limas profile system GT e profile GT series X por difracção de raios-X. Mestrado Integrado em Medicina Dentária (FMD-UL). Supervision: Sancho Correia (FMD-UL), F.M. Braz Fernandes.• Luis Alberty Vieira. Soldadura Laser de Ligas com memória de forma. Mestrado em Engª Mecânica, FCT/UNL. Supervisor: Rosa Miranda (DEMI). Co-supervisor: FM Braz Fernandes.• Magno Dinis Dias de Sousa. Caracterização do comportamento mecânico em rotação-flexão de limas ProSystemGT e Profile GT series X. Estudo comparativo in vitro. Mestrado Integrado em Medicina Dentária (FMD-UL). Supervision: Sancho Correia (FMD-UL), F.M. Braz Fernandes.• Luis Manuel Alberty Vieira (Eng.ª Mecânica, DEMI). “Soldadura laser de ligas com memória de forma”. Supervision: Rosa Miranda (DEMI), F. M. Braz Fernandes, 10/11/2010.• João Pedro Oliveira (Engª Materiais, DCM) “Correlation Between the Mechanical Cycling Behavior and Microstructure in Laser Welded Joints Using NiTi Shape Memory Alloys”, . Supervision: F. M. Braz Fernandes, Rosa Miranda (DEMI), 30/07/2012.• Alain Pereira (Engª Materiais, DCM) “Deformação plástica severa por ECAP de ligas com memória de forma”, Supervision: F. M. Braz Fernandes, K.K. Mahesh, 14/05/2013.

Advanced Training

PhD thesis completed :

• Andersan dos Santos Paula. “Tratamentos termomecânicos de ligas do sistema Ni-Ti. Caracterização estrutural e optimização das propriedades associadas ao efeito de memória de forma”. FCT/UNL, May 2006 (340 pp). Supervisor: F. M. Braz Fernandes.• Christian Mariani Lucas dos Santos, “Ligas Ni-Ti ricas em Ni: Tratamento Térmico, Termomecânico e Efeito de Micromemória de forma”, IME - Instituto Militar de Engenharia, 29/11/2006. Supervisors: Carlos Sérgio da Costa Viana (IME), F.M. Braz Fernandes.• Production and characterization of Cu-Al-Ni shape memory alloys. Carmela Gurau. UniversityGalati, Romania, 29/07/2008. Supervisors: E. Drugescu (Galati), F. M. Braz Fernandes. • Production and characterization of NiTi thin films. R.M.S. Martins. FCT/UNL, 17/10/2008. Supervisors: F. M. Braz Fernandes, Norbert Schell (DESY, Hamburg, Germany). • Comportamento em serviço de limas endodônticas de Ni-Ti. Sancho Vilaverde Correia. Scheduledfor September 2009. Faculdade de Medicina Dentária (Univ de Lisboa). Supervisors: F. M. Braz Fernandes, Luis Pires Lopes (FMDUL).

Advanced Training

•“Structural Characterisation of NiTi Thin Film Shape Memory Alloys”. Francisco M. Braz Fernandes, Rui Martins, M.ª Teresa Nogueira, Rui J. C. Silva, Patrícia Nunes, Daniel Costa, Isabel Ferreira, Rodrigo Martins. Sensors and Actuators, 99/1-2 (2002) pp. 55-58.•“In-situ GIXRD characterization of the crystallization of Ni-Ti sputtered thin films”. Rui M. S. Martins, Rui J. C. Silva, Francisco M. Braz Fernandes, Luis Pereira, Paulo R. Gordo, Manuel J. P. Maneira, Norbert Schell. Materials Science Forum 455-456 (2004) pp. 342-345.•“Real-time and in-situ structural design of functional NiTi SMA thin films”. N. Schell, R.M.S. Martins, F.M. Braz Fernandes. Applied Physics A - Materials Science & Processing, vol. 81, nr 7 (2005) pp. 1441-1445.•“Structural in-situ studies of Shape Memory Alloy (SMA) Ni-Ti thin films”. R.M.S. Martins, F.M. Braz Fernandes, R.J.C. Silva, M. Beckers, N. Schell. Nuclear Instruments & Methods Physics B 238 (2005) pp. 319-322.•“Optical Emission Spectroscopy study of magnetron assisted Ni-Ti dc sputtering”. Marcia Silva, F. M. Braz Fernandes, Paulo Gordo, Manuel Maneira. Materials Science Forum 514-516 (2006) pp. 1274-1278.•“In-situ observation of Ni-Ti thin film growth by synchrotron radiation scattering”. Rui M. S. Martins, F. M. Braz Fernandes, R. J. C. Silva, M. Beckers, N. Schell. Materials Science Forum 514-516 (2006) pp. 1588-1592.•“The influence of a poly-Si intermediate layer on the crystallization behaviour of Ni-Ti SMA magnetron sputtered thin films”. R.M.S. Martins, F.M. Braz Fernandes, R.J.C. Silva, L. Pereira, P.R. Gordo, M.J.P. Maneira, M. Beckers, A. Muecklich, and N. Schell. Applied Physics A - Materials Science & Processing 83 (2006) pp. 139-145.•“Growth of sputter-deposited Ni-Ti thin films: effects of a SiO2 buffer layer”. R.M.S Martins, N. Schell, M. Beckers, K.K. Mahesh, R.J.C. Silva, F.M. Braz Fernandes. Applied Physics A - Materials Science & Processing 84 (2006) pp. 285-289.•“In-situ study of Ni-Ti thin film growth on a TiN intermediate layer by x-ray diffraction”. R.M.S. Martins, N. Schell, R.J.C. Silva, L. Pereira, K.K. Mahesh, F.M. Braz Fernandes. Sensors and Actuators B: Chemical 126 (2007) pp. 332-337.•“Study of graded Ni-Ti Shape Memory Alloy film growth on Si(100) substrate”. R.M.S. Martins, A. Mücklich, H. Reuther, M. Beckers, N. Schell, R.J.C. Silva, L. Pereira, and F.M. Braz Fernandes. Applied Physics A - Materials Science & Processing 91(2008) pp. 291-299.•“Role of the substrate on the growth of Ni-Ti sputtered thin films”. R.M.S. Martins, N. Schell, M. Beckers, R.J.C. Silva, K.K. Mahesh, F.M. Braz Fernandes. Materials Science and Engineering A 481–482 (2008) pp. 626–629.•“Characterization of sputtered Shape Memory Alloy Ni-Ti films by cross-sectional TEM and SEM”. R. M.S. Martins, A. Mücklich, N. Schell, R.J.C. Silva, K.K. Mahesh, F.M. Braz Fernandes. Microscopy and Microanalysis 14 (2008) pp. 85-86.•“Development of sputtered Shape Memory Alloy (SMA) Ni–Ti films for actuation in ice cooled environments”. R.M.S. Martins, N. Schell, P.R. Gordo, M.J.P. Maneira, R.J.C. Silva, F.M. Braz Fernandes. Vacuum 83 (2009) pp. 1299-1302.•“Structural evolution of magnetron sputtered Shape Memory Alloy Ni-Ti films”, R.M.S. Martins, N. Schell, J.v. Borany, K.K. Mahesh, R.J.C. Silva, F.M. B. Fernandes. Vacuum 84 (2010) pp. 913-919.•“Texture development and phase transformation behaviour of sputtered Ni-Ti Films”. R.M.S. Martins, N. Schell, R.J.C. Silva, L. Pereira, K. K. Mahesh, F.M. Braz Fernandes. Journal of MaterialsEngineering and Performance 18 (2009) pp. 543-547.•“Texture development, microstructure and phase transformation characteristics of sputtered Ni-Ti Shape Memory Alloy films on TiN<111>”. Rui M.S. Martins, Norbert Schell, H. Reuther, L. Pereira, K. Mahesh, Rui Silva, F.M. Braz Fernandes. Thin Solid Films 519 (2010) pp. 122–128.•“Simultaneous probing of phase transformations in Ni-Ti thin film Shape Memory Alloy by synchrotron radiation-based X-ray diffraction and Electrical Resistivity”. F.M. Braz Fernandes, K.K. Mahesh, R.M.S. Martins, R.J.C. Silva, C. Baehtz, J. von Borany. Materials Characterization 76 (2013) pp. 35-38.

•Contacts:e-mail: fbf@fct.unl.ptURL: http://bf.no.sapo.pt

Publications Ni-Ti thin films

•“Effect of thermal cycling on the transformation temperatures of a Ni-Ti shape memory alloy”. A.S. Paula, J.P.H.G. Canejo, Rui J. C. Silva, F.M. Braz Fernandes. Materials Science Forum 455-456 (2004) pp. 346-349.•“Effect of thermal cycling on the transformation temperature ranges of a Ni-Ti shape memory alloy”. A.S. Paula, J.P.H.G. Canejo, R.M.S. Martins, F.M. Braz Fernandes. Materials Science and Engineering A 378/1-2 (2004) pp. 92-96.•“In Situ High Temperature Texture Characterisation in NiTi Shape Memory Alloy Using Synchrotron Radiation”. A.S. Paula, K.K. Mahesh, F.M. Braz Fernandes, R.M.S. Martins, A.M.A. Cardoso, N. Schell. Materials Science Forum, 495-497 (2005) pp. 125-130.•“Structural Evolution on Thermal Cycling in Ti-Rich NiTi SMA”. A.S. Paula, J.P.H.G. Canejo, N. Schell, F.M. Braz Fernandes. Nuclear Instruments & Methods Physics Research B 238 (2005) pp. 111-114.•“Micromemory effects involved during martensitic transformation in Ni-rich NiTi alloys”. K. Mahesh, F. M. Braz Fernandes, C. M. L. Santos. Materials Science Forum 514-516 (2006) pp. 1668-1672.•“Study of the textural evolution in Ti-rich NiTi using synchrotron radiation”. A.S. Paula, J.H.P.G. Canejo, K.K. Mahesh, R.J.C. Silva, F.M. Braz Fernandes, R.M.S. Martins, A.M.A. Cardoso, N. Schell. Nuclear Instruments & Methods Physics B 246 (2006) pp. 206-210.•“One- and Two-Step Phase Transformation in Ti-rich NiTi Shape Memory Alloy”. A.S. Paula, K.K. Mahesh, C.M.L. dos Santos, J.P.H.G. Canejo, F.M. Braz Fernandes. International Journal of Applied Electromagneticsand Mechanics 23(1-2) (2006) pp. 25-32.•“X-ray Diffraction study of the phase transformations in NiTi shape memory alloy”. J. Uchil, F. M. Braz Fernandes, K. K. Mahesh. Materials Characterization 58(3) (2007) pp. 243-248.•“Electric resistance variation of NiTi SMA wires in thermomechanical tests: Experiments and simulation”. V. Novák, P. Šittner, G.N. Dayananda, F.M. Braz-Fernandes, K. K. Mahesh. Materials Science and EngineeringA 481–482 (2008) pp. 127–133.•“Thermomechanical behavior of Ti-rich NiTi shape memory alloys”. A.S. Paula, K.K. Mahesh, C.M.L. dos Santos, F.M. Braz Fernandes, C.S. da Costa Viana. Materials Science and Engineering A 481-482 (2008) pp. 146-150.•“Evolution of phase transformations after multiple steps of marforming in Ti-rich NiTi SMA”. A.S. Paula, K.K. Mahesh, F.M. Braz Fernandes. European Physical Journal 158 (2008) pp. 45–51.•“Mechanical behaviour of ausformed and marformed Ti-rich Ni-Ti shape memory alloys”. A.S. Paula, K.K. Mahesh, C.M.L. dos Santos, F.M. Braz Fernandes, C.S. da Costa Viana. Materials Science Forum 587-588 (2008) pp. 635-639.“Evolution of phase transformations after multiple steps of marforming in Ti-rich NiTi SMA”. A.S. Paula, K.K. Mahesh, F.M. Braz Fernandes. European Physical Journal 158 (2008) pp. 45–51.“The transformation behaviour of bulk nanostructured NiTi alloys”. F. Neves, F.M. Braz Fernandes, I. Martins, J.B. Correia, M. Oliveira, E. Gaffet, T.-Y. Wang, M. Lattemann, J. Suffner, H. Hahn. Smart Materials andStructures 18 (2009) 115003 (9pp).“XRD study of the transformation characteristics of severely plastic deformed Ni-Ti SMAs”. F.M. Braz Fernandes, K.K. Mahesh, R.J.C. Silva, C. Gurau, G. Gurau. Phisica Status Solidi 7 (2010) pp. 1348-1350.“Phase Transformation in Ni-Ti Shape Memory and Superelastic Alloys Subjected to High Pressure Torsion”. K.K. Mahesh, F.M. Braz Fernandes, G. Gurau. Advanced Materials Research 123-125 (2010) pp. 1007-1010.“Phase transformation and structural study on the severely plastic deformed NiTi alloys”. K.K. Mahesh, F.M. Braz Fernandes, R.J.C. Silva, G. Gurau. Physics Procedia, 10 (2010) pp. 22-27.“Structural Transitions in a Co2 Ni Ga Ferromagnetic Shape Memory Alloys”. C.M. Craciunescu, K.K. Mahesh, R.J.C. Silva, F.M. Braz Fernandes. Solid State Phenomena, 172-174 (2010) pp. 202-207.“Parametric Optimization of Ti-Ni Powder Mixtures Produced by Mechanical Alloying”. Filipe Neves, Franscisco M. Braz Fernandes, Isabel Martins, José Brito Correia. Journal of Alloys and Compound 509S (2011) S271–S274.“Mechanical behaviour of Nd:YAG laser welded superelastic NiTi”. L. Alberty Vieira, F.M. Braz Fernandes, R.M. Miranda, R.J.C. Silva, L. Quintino, A. Cuesta, J.L. Ocaña. Materials Science and Engineering A 528 (2011) pp. 5560-5565, doi:10.1016/j.msea.2011.03.089.“Stability in Phase Transformation After Multiple Steps of Marforming in Ti-Rich Ni-Ti Shape Memory Alloy”. A.S. Paula, K.K. Mahesh, F.M. Braz Fernandes. Journal of Materials Engineering and Performance 20 (2011) pp. 771-775. DOI: 10.1007/s11665-011-9920-5.“Structural study of extruded Cu Al13 Ni4 shape memory alloy”. F. M. Braz Fernandes, C.Gurau, K. K. Mahesh, R. J. C. Silva, G. Gurau. Metalurgia International 16 (2011) pp. 19-23.“Laser beam interaction with Ni–Mn–Ga ferromagnetic shape memory alloys”. C.M. Craciunescu, R.M.Miranda, R.J.C.Silva, E.Assunção, F.M.BrazFernandes Optics and Lasers in Engineering 49(2011) pp. 1289–1293.“Stability of thermal-induced phase transformations in the severely deformed equiatomic Ni–Ti alloys”. K. K. Mahesh, F. M. Braz Fernandes, G. Gurau. Journal of Materials Science 47-16(2012) pp. 6005-6014.“Role of oxygen and nitrogen in mechanical alloying mechanism of Ni–Ti powder mixtures”. F. Neves, F. M. Braz Fernandes, I. Martins and J. B. Correia. Powder Metallurgy 55-4(2012) pp. 268-272.“Effect of load cycling on the phase transformations in Ni–Ti wires for civil engineering applications”. M. Branco, L. Guerreiro, K.K. Mahesh, F.M. Braz Fernandes. Construction and Building Materials 36 (2012) pp. 508–519.“Graded transitions in Ni-Ti shape memory alloys processed by severe plastic deformation”. C. M. Craciunescu, F. M. Braz Fernandes. Functional Materials Letters vol 5 4(2012) 1250049 (4 pgs).“Analyzing mechanical properties and non-destructive characteristics of brazed joints of NiTi shape memory alloys to carbon steel rods”. T.G. Santos, F.M. Braz Fernandes, G. Bernardo, R.M. Miranda. InternationalJournal of Advanced Manufacturing Technology 66 (2013) pp. 787-793.

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