Materiale electrotehnice noi

Nanodielectrici

Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009-2010, master IPE, anul I Prof.dr.ing.Florin Ciuprina

Structura disciplinei

Capitolul 1 2 3 Conţinutul

Fenomene in materialele electrotehnice

1.1. Conductia electrica 1.2. Polarizarea electrica 1.3. Magnetizarea materialelor 1.4. Pierderi in materialele electrotehnice

Materiale conductoare noi

2.1. Materiale conductoare clasice 2.2. Materiale supraconductoare 2.3. Conductori organici si nanotuburi de carbon 2.4. Materiale pentru realizarea de memristori 2.5. Aplicatii moderne ale materialelor conductoare

Materiale semiconductoare noi

3.1. Materiale semiconductoare clasice 3.2. Polimeri semiconductori 3.3. Materiale semiconductoare nanostructurate 3.4. Aplicatii moderne (celule solare, microprocesoare de inalta frecventa, ecrane TV, laseri) 4 5

Materiale dielectrice noi

4.1. Evolutia materialelor dielectrice 4.2. Straturi subtiri 4.3. Nanodielectrici 4.4. Oxizi metalici 4.5. Aplicatii

Materiale magnetice noi

5.1. Evolutia materialelor magnetice 5.2. Materiale magnetice amorfe 5.3. Materiale magnetice nanostructurate (nanocristaline, organice) 5.4. Fire si filme subtiri din materiale magnetice 5.5. Aplicatii moderne (miezuri magnetice, memorii, hard-discuri, carduri magnetice)

Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009-2010, master IPE, anul I

Nanodielectrici

Nanodielectrici

Nanodielectrici

1. Polymer nanocomposites as dielectrics 2. Characterisation: nanostructure, electrical & mecanical properties, thermal stability 3. Numerical modeling of nanodielectrics 4. Possible applications of polymer nanocomposites in Electrical Engineering

Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009-2010, master IPE, anul I

Nanodielectrici

Nanodielectrici

1. Polymer nanocomposites as dielectrics 2. Characterisation: nanostructure, electrical & mecanical properties, thermal stability 3. Numerical modeling of nanodielectrics 4. Possible applications of polymer nanocomposites in Electrical Engineering

Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009-2010, master IPE, anul I

Nanodielectrici

1994 : Symbolic birth of Nanodielectrics: John Lewis published the paper “ Nanometric Dielectrics ” in IEEE Transactions on Dielectrics and Electrical Insulation Nanodielectrics ≈ Polymer nanocomposites with dielectric properties: polymers (PA, PE, PP, PVC, epoxy resins, silicone rubbers) + nano-fillers (LS, SiO 2 , TiO 2 , Al 2 O 3 ) * 1 to 100 nm in size, * 1 to 10 wt% in content * homogeneously dispersed in the polymer matrix.

2002 : First experimental data on nanometric dielectrics.

2002-2008 : Articles in the field reported that



nano-filler addition has the potential of improving the electrical, mechanical and thermal properties as compared to the neat polymers;



polymer nanocomposites are increasingly desirable as coatings, structural and packaging materials in automobile, civil, aerospace and electrical engineering.

2006-2008 : Project CEEX- PoNaDIP

Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009-2010, master IPE, anul I

Steps of the research Design & Realizing Structure-Property Relationship Characterization Modeling

Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009-2010, master IPE, anul I

Nanodielectrici

Nanodielectrici

Design & realizing

Research at UPB-ELMAT:  14 combinations polymer – nanofiller  Plane samples 10 X 10 cm 2 , thickness ≤ 1 mm  Nanofillers:1 to 100 nm in size, 1 to 10 wt% in content, and homogeneously dispersed in the polymer matrix

POLYMER NANOFILLER

thermoplastic organic thermoset inorganic

Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009-2010, master IPE, anul I

Design & realizing

Nanodielectrici    

Nanocomposites investigated

  PP, PVC and LDPE with SiO 2 nanoparticles of 15 nm diameter PP, PVC and LDPE with TiO 2 nanoparticles of 15 nm diameter PP, PVC and LDPE with Al 2 O 3 nanoparticles of 40 nm diameter nanofillers content: 2, 5 and 10 wt%. Manufacturing by direct mixing method Samples for electrical tests: plaques of square shape (10 x 10 cm 2 ) having the thickness of 0.5 mm.

Installation for nanocomposite manufacturing

Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009-2010, master IPE, anul I

Nanodielectrici

Nanodielectrici

1. Polymer nanocomposites as dielectrics 2. Characterisation: nanostructure, electrical & mecanical properties, thermal stability 3. Numerical modeling of nanodielectrics 4. Possible applications of polymer nanocomposites in Electrical Engineering

Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009-2010, master IPE, anul I

Nanostructure SEM at ICECHIM LDPE - SiO 2

Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009-2010, master IPE, anul I

Nanodielectrici

Characterization

Nanodielectrici

Electrical properties Dielectric Spectroscopy at UPB/ELMAT

 real part of the permittivity (  

r

)  loss tangent (tan δ)  dielectric spectroscopy: Novocontrol ALPHA-A Analyzer (3) in combination with an Active Sample Cell ZGS (4) and a Temperature Control System Novotherm (5)  frequency range 10 -3 – 10 6 Hz

Characterization

Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009-2010, master IPE, anul I

Nanodielectrici

Electrical properties Dielectric Spectroscopy at UPB/ELMAT

2.7

2.6

2.5

2.4

2.3

PP PP + TiO 2 - 15 nm - 5% PP + SiO 2 - 15 nm - 5% PP + Al 2 O 3 - 40 nm - 5% 2.2

2.1

2.0

10 -4 10 -3 10 -2 10 -1 10 0 10 1 10 2 f [Hz] 10 3 10 4 10 5 10 6 10 7 10 -1 10 -2 10 -3 PP PP + TiO 2 - 15 nm - 5% PP + SiO 2 - 15 nm - 5% PP + Al 2 O 3 - 40 nm - 5% 10 -4 10 -4 10 -3 10 -2 10 -1 10 0 10 1 f [Hz] 10 2 10 3 10 4 10 5 10 6

Results for PP nanocomposites with Al 2 O 3 , SiO 2 at T = 300 K and TiO 2 fillers

Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009-2010, master IPE, anul I

Nanodielectrici

Electrical properties Dielectric Spectroscopy at UPB/ELMAT

35 30 25 20 15 PCV PCV + TiO 2 - 15 nm - 5 % PCV + SiO 2 - 15 nm - 5 % PCV + Al 2 O 3 - 40 nm - 5 % 10 0 PCV PCV + TiO 2 - 15 nm - 5 % PCV + SiO 2 - 15 nm - 5 % PCV + Al 2 O 3 - 40 nm - 5 % 10 10 -1 5 0 10 -4 10 -3 10 -2 10 -1 10 0 10 1 10 2 10 3 10 4 10 5 10 6 10 7 10 -4 10 -3 10 -2 10 -1 10 0 10 1 10 2 f [Hz] f [Hz]

Results for PVC nanocomposites with Al 2 O 3 , SiO 2 at T = 300 K and TiO 2 fillers

10 3 10 4 10 5 10 6 10 7

Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009-2010, master IPE, anul I

Nanodielectrici

Electrical properties Dielectric Spectroscopy at UPB/ELMAT

2.6

2.5

PEJD PEJD + MP PEJD + MP + SiO 2 - 15 nm - 2 % PEJD + MP + Al 2 O 3 - 40 nm - 2 % PEJD + MP + TiO 2 - 15 nm - 2 % 10 1 10 0 10 -1 PEJD PEJD + MP PEJD + MP + SiO 2 - 15 nm - 2 % PEJD + MP + Al 2 O 3 - 40 nm - 2 % PEJD + MP + TiO 2 - 15 nm - 2 % 2.4

10 -2 2.3

10 -3 2.2

2.1

10 -4 10 -3 10 -2 10 -1 10 0 10 1 10 2 f [Hz] 10 3 10 4 10 5 10 6 10 7 10 8 10 -4 10 -4 10 -3 10 -2 10 -1 10 0 10 1 f [Hz] 10 2

Results for LDPE nanocomposites with Al 2 O 3 , SiO 2 at T = 300 K and TiO 2 fillers

10 3 10 4 10 5 10 6

Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009-2010, master IPE, anul I

Nanodielectrici

Electrical properties Dielectric Spectroscopy at UPB/ELMAT

PEJD + MP PEJD + MP + Al 2 O 3 - 40 nm - 2 % PEJD + MP + Al 2 O 3 - 40 nm - 5 % PEJD + MP + Al 2 O 3 - 40 nm - 10 % 2.5

10 -1 PEJD + MP PEJD + MP + Al 2 O 3 - 40 nm - 2 % PEJD + MP + Al 2 O 3 - 40 nm - 5 % PEJD + MP + Al 2 O 3 - 40 nm - 10 % 2.4

10 -2 2.3

10 -3 2.2

10 -4 10 -3 10 -2 10 -1 10 0 10 1 10 2 f [Hz] 10 3 10 4 10 5 10 6 10 7 10 -4 10 -3 10 -2 10 -1 10 0 10 1 f [Hz] 10 2 10 3 10 4 10 5 10 6

Results for LDPE - Al 2 O 3 nanocomposites, for different filler concentration, at T = 300 K

Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009-2010, master IPE, anul I

Nanodielectrici

Electrical properties Absorption-Resorption Currents at UPB/ELMAT Resistivity

 : Keithley 6517 Electrometer in combination Keithley 8009 Test Fixture

Characterization

Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009-2010, master IPE, anul I

Electrical properties Absorption-Resorption Currents at UPB/ELMAT

Nanodielectrici

Characterization

Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009-2010, master IPE, anul I

Nanodielectrici

Electrical properties Resistivity of LDPE nanocomposites at UPB/ELMAT

Material Unfilled LDPE LDPE with 5 wt% nano-SiO 2 LDPE with 5 wt% nano-Al 2 O 3 LDPE with 5 wt% nano-TiO 2 Relative volume resistivity at

10 V

1 39.39

6.08

4.09

Relative volume reisistivity at

500 V

1 0.54

0.19

0.72

Characterization

Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009-2010, master IPE, anul I

Nanodielectrici

18 17 16 15 14 13 12 13 12 11 10 16 15 14 Mechanical properties at ICECHIM

 LDPE – SiO 2 and LDPE – Al 2 O 3 nanocomposites  According to ISO 527 on specimens type IB (5 specimens for each test) with 50 mm/min for tensile strength and 2 mm/min for modulus of elasticity.

2,8 550 Characterization 500 2,4 450 2,0 400 1,6 350 300 1,2 0,8 250

0 2 4 6 8 Nano SiO 2 concentration [%] 10

0 2 4 6 8

Nano SiO 2 concentration [%]

10 2,8 550 500 450 400 350 10 300 250 2,4 2,0 1,6 1,2 0,8 0 2 4 6 8 0 2 4 6 8 10

Nanodielectrici

Nanodielectrici

1. Polymer nanocomposites as dielectrics 2. Characterisation: nanostructure, electrical & mecanical properties, thermal stability 3. Numerical modeling of nanodielectrics 4. Possible applications of polymer nanocomposites in Electrical Engineering

Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009-2010, master IPE, anul I

Nanodielectrici

Numerical model at UPB/ELMAT

Ideas multi-core model (Tanaka)

Modeling

Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009-2010, master IPE, anul I

Nanodielectrici

Numerical model at UPB/ELMAT

3D Model

Sample features: nanoparticle matrix

- thickness 1 mm - diameter of the nanoparticle 40 nm - thickness if the interface 10 nm - filler content 5% - relative permittivities: nanoparticle/interface/matrix = 10/6/2.2

Modeling elementary capacitor interface

Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009-2010, master IPE, anul I

Numerical model at UPB/ELMAT

Electrostatic field

div (



grad V) = 0

V – electric scalar potential  – electric permittivity

Modeling

Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009-2010, master IPE, anul I

Nanodielectrici

Nanodielectrici

Numerical model at UPB/ELMAT

Computational domain – in FLUX 3D

Main data of the numerical model:

- dimension of the elementary cube 120 nm along each axis - nanoparticle diameter 40 nm - thickness of the interface 10 nm - concentration of nanoparticles 5% - relative electric permittivities: nanoparticle/interface/matrix = 10/6/2.2 - applied voltage 0.02 V

Modeling

Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009-2010, master IPE, anul I

Nanodielectrici

Numerical model at UPB/ELMAT

Descretization mesh - finite element method

Size of the mesh:

- 6784 nodes 41770 volume finite elements -- tethrahedral elements

Modeling

Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009-2010, master IPE, anul I

Nanodielectrici

Numerical model at UPB/ELMAT

Computation of the equivalent permittivity

1) Computation of the electric energy stored in the material samples:

W

  Ω

D



E

2 dV

2) Computation of the capacitance of the elementar capacitor by using two different methods:

C



2W U 2 C



ε 0 ε r d eq A

3) Evaluation of the equivalent rel. electric permittivity



r eq

:

ε r eq



2Wd ε 0 AU 2

Modeling

Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009-2010, master IPE, anul I

Numerical model at UPB/ELMAT

Numerical results Electric scalar potential – color map

Nanodielectrici

Without nanoparticles Modeling With nanoparticles

Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009-2010, master IPE, anul I

Numerical model at UPB/ELMAT

Numerical results Electric field strength – color map

Nanodielectrici

Without nanoparticles Modeling With nanoparticles

Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009-2010, master IPE, anul I

Nanodielectrici

Numerical model at UPB/ELMAT

Parametric study

• • • • • •

filler content

fc

diameter of the nanoparticle

dn

thickness of the interface

ti

relative permittivity of the polymer matrix



rm

relative permittivity of the interface



ri

relative permittivity of the nanofiller



rn Modeling

Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009-2010, master IPE, anul I

Nanodielectrici

Numerical model at UPB/ELMAT

Numerical results equivalent permittivity vs. interface permittivity



re = f(



ri ) fc = 5% dn = 40 nm ti = 10 nm



rm = 2.2



rn = 10



ri = 3; 4; 5; 6; 7; 8 Modeling

2.5

2.45

2.4

2.35

2.3

2.25

2.2

2.15

2.1

2.05

2 3 4 5 6

epsr interface

7 8

Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009-2010, master IPE, anul I

Nanodielectrici

Numerical model at UPB/ELMAT

Numerical results equivalent permittivity vs. the thickness of the interface layer



re = f(ti) fc = 5% dn = 40 nm ti = 5; 10; 15; 20 nm

r

vi = 0



rm = 2.2



rn



ri = 10 = 4 Modeling

2.5

2.45

2.4

2.35

2.3

2.25

2.2

2.15

2.1

2.05

2 5 10 15

thickness of the interface [nm]

Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009-2010, master IPE, anul I

20

Nanodielectrici

Numerical model at UPB/ELMAT



re = f(dn) fc = 5% dn = 10; 20; 30; 40; 50 nm ti = 10 nm



rm = 2.2



rn = 10



ri = 4 Modeling

Numerical results equivalent permittivity vs. the diameter of the nanoparticle

2.5

2.45

2.4

2.35

2.3

2.25

2.2

2.15

2.1

2.05

2 10 20 30 40

diameter of the nanoparticle [nm]

50

Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009-2010, master IPE, anul I

Nanodielectrici

Numerical model at UPB/ELMAT

Numerical results equivalent permittivity vs. nanoparticle permittivity



re = f(



rn ) fc = 5% dn = 40 nm ti = 10 nm



rm = 2.2



rn = 4; 10



ri = 2.2 Modeling

2.5

2.4

2.3

2.2

2.1

2 4 6

epsr nanoparticle

8 10

Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009-2010, master IPE, anul I

Numerical model at UPB/ELMAT

Particle agglomeration

Nanodielectrici

Modeling

Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009-2010, master IPE, anul I

Numerical model at UPB/ELMAT

Particle agglomeration + isolated particles

Nanodielectrici

Modeling

Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009-2010, master IPE, anul I

Nanodielectrici

Nanodielectrici

1. Polymer nanocomposites as dielectrics 2. Characterisation: nanostructure, electrical & mecanical properties, thermal stability 3. Numerical modeling of nanodielectrics 4. Possible applications of polymer nanocomposites in Electrical Engineering

Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009-2010, master IPE, anul I

Nanodielectrici

Nanocomposite applications in Electrical engineering at ETN-EE

 Manufacturing and testing of coil holders  Selected materials: LDPE + Al 2 O 3 and LDPE + SiO 2 with 2% filler content.

 Coil holders made from selected nanocomposites have better behaviour as compared with those from the neat polymer (dielectric strength, mecanical properties and, obviously, flame retardancy)

Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009-2010, master IPE, anul I