Materiale electrotehnice noi Nanodielectrici Facultatea de Inginerie Electrica

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

Nanodielectrici Structura disciplinei Capitolul Conţinutul 1 Fenomene in materialele electrotehnice 1. 1. Conductia electrica 1. 2. Polarizarea electrica 1. 3. Magnetizarea materialelor 1. 4. Pierderi in materialele electrotehnice 2 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 3 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 Materiale dielectrice noi 4. 1. Evolutia materialelor dielectrice 4. 2. Straturi subtiri 4. 3. Nanodielectrici 4. 4. Oxizi metalici 4. 5. Aplicatii 5 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 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 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, Si. O 2, Ti. O 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- Po. Na. DIP Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009 -2010, master IPE, anul I

Steps of the research Design & Realizing Characterization Structure-Property Relationship Modeling Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009 -2010, master IPE, anul I Nanodielectrici

Nanodielectrici Design & realizing Research at UPB-ELMAT: q 14 q 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 q POLYMER NANOFILLER thermoplastic organic thermoset inorganic Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009 -2010, master IPE, anul I

Nanodielectrici Nanocomposites investigated Design & realizing q PP, PVC and LDPE with Si. O 2 nanoparticles of 15 nm diameter q PP, PVC and LDPE with Ti. O 2 nanoparticles of 15 nm diameter q PP, PVC and LDPE with Al 2 O 3 nanoparticles of 40 nm diameter q nanofillers content: 2, 5 and 10 wt%. q Manufacturing by direct mixing method q 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 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 Nanostructure SEM at ICECHIM Characterization LDPE - Si. O 2 Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009 -2010, master IPE, anul I

Nanodielectrici Electrical properties Dielectric Spectroscopy at UPB/ELMAT Characterization q real part of the permittivity ( ) q loss tangent (tan δ) q dielectric spectroscopy: Novocontrol ALPHA-A Analyzer (3) in combination with an Active Sample Cell ZGS (4) and a Temperature Control System Novotherm (5) q frequency range 10 -3 – 106 Hz Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009 -2010, master IPE, anul I

Nanodielectrici Electrical properties Dielectric Spectroscopy at UPB/ELMAT Results for PP nanocomposites with Al 2 O 3, Si. O 2 and Ti. O 2 fillers at T = 300 K Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009 -2010, master IPE, anul I

Nanodielectrici Electrical properties Dielectric Spectroscopy at UPB/ELMAT Results for PVC nanocomposites with Al 2 O 3, Si. O 2 and Ti. O 2 fillers at T = 300 K Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009 -2010, master IPE, anul I

Nanodielectrici Electrical properties Dielectric Spectroscopy at UPB/ELMAT Results for LDPE nanocomposites with Al 2 O 3, Si. O 2 and Ti. O 2 fillers at T = 300 K Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009 -2010, master IPE, anul I

Nanodielectrici Electrical properties Dielectric Spectroscopy at UPB/ELMAT 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 q: Keithley 6517 Electrometer in combination Keithley 8009 Test Fixture Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009 -2010, master IPE, anul I Characterization

Nanodielectrici Electrical properties Absorption-Resorption Currents at UPB/ELMAT 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 with 5 wt% nano-Si. O 2 LDPE with 5 wt% nano-Al 2 O 3 LDPE with 5 wt% nano-Ti. O 2 Relative volume resistivity at 10 V 1 Relative volume reisistivity at 500 V 1 39. 39 0. 54 6. 08 0. 19 4. 09 0. 72 Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009 -2010, master IPE, anul I Characterization

Nanodielectrici Mechanical properties at ICECHIM q LDPE – Si. O 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. q Characterization Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009 -2010, master IPE, anul I

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 3 D Model Sample features: 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 nanoparticle matrix Modeling elementary capacitor interface Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009 -2010, master IPE, anul I

Nanodielectrici Numerical model at UPB/ELMAT Electrostatic field div (e grad V) = 0 V – electric scalar potential e – electric permittivity Modeling Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009 -2010, master IPE, anul I

Nanodielectrici Numerical model at UPB/ELMAT Computational domain – in FLUX 3 D 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: 2) Computation of the capacitance of the elementar capacitor by using two different methods: 3) Evaluation of the equivalent rel. electric permittivity Modeling Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009 -2010, master IPE, anul I er eq :

Nanodielectrici Numerical model at UPB/ELMAT Numerical results Electric scalar potential – color map Without nanoparticles Modeling With nanoparticles Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009 -2010, master IPE, anul I

Nanodielectrici Numerical model at UPB/ELMAT Numerical results Electric field strength – color map Without nanoparticles With nanoparticles Modeling 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 erm relative permittivity of the interface eri relative permittivity of the nanofiller ern Modeling Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009 -2010, master IPE, anul I

Nanodielectrici Numerical model at UPB/ELMAT ere = f(eri) Numerical results equivalent permittivity vs. interface permittivity fc = 5% dn = 40 nm ti = 10 nm erm = 2. 2 ern = 10 eri = 3; 4; 5; 6; 7; 8 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. the thickness of the interface layer ere = f(ti) fc = 5% dn = 40 nm ti = 5; 10; 15; 20 nm rvi = 0 erm = 2. 2 ern = 10 eri = 4 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. the diameter of the nanoparticle ere = f(dn) fc = 5% dn = 10; 20; 30; 40; 50 nm ti = 10 nm erm = 2. 2 ern = 10 eri = 4 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. nanoparticle permittivity ere = f(ern) fc = 5% dn = 40 nm ti = 10 nm erm = 2. 2 ern = 4; 10 eri = 2. 2 Modeling Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009 -2010, master IPE, anul I

Nanodielectrici Numerical model at UPB/ELMAT Particle agglomeration Modeling Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009 -2010, master IPE, anul I

Nanodielectrici Numerical model at UPB/ELMAT Particle agglomeration + isolated particles Modeling Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009 -2010, master IPE, anul I

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 q Manufacturing and testing of coil holders q Selected materials: LDPE + Al 2 O 3 and LDPE + Si. O 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) q Facultatea de Inginerie Electrica, Materiale electrotehnice noi, 2009 -2010, master IPE, anul I