UNIVERSITY OF CINCINNATI NCA&T, AFIT STRUCTURAL NANOSCIENCE TO ACHIEVE BREAKTHROUGH AIR VEHICLE CAPABILITIES

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1 UNIVERSITY OF CINCINNATI NCA&T, AFIT STRUCTURAL NANOSCIENCE TO ACHIEVE BREAKTHROUGH AIR VEHICLE CAPABILITIES Smart Materials Nanotechnology Laboratory Mark J. Schulz, Vesselin N. Shanov, Yun Yeo-Heung, Goutham Kirikera Department of Mechanical Engineering, Cincinnati, OH Phone: (513) , Department of Chemical and Materials Engineering Cincinnati, OH Phone: (513) ,

2 Outline Synthesis of Carbon Nanotube Arrays Structural Reinforcement, Active Structures, Thermal and Fluids Applications Structural Health Monitoring Conclusions UC Institute for Nanoscale Science and Technology

3 Synthesis of Carbon Nanotube Arrays UC Institute for Nanoscale Science and Technology

4 UC Modified Thermal CVD Process for Nanotube Synthesis Bubbler Quartz Tube Heating Coil Gas Out Ar C 2 H 2 CH 4 CH 2 H 2 Carbon Precursors Quartz Boat Mass Flow Controllers CH 4 (g) Heating Coil T H 2 C(s) + 2H 2 (g) Substrate QMS Substrate: Si wafer or Powder Catalyst: Fe, or Co, or Ni

5 Substrate Preparation is critical for Carbon Nanotube Array Synthesis using Chemical Vapor Deposition (CVD)

6 Aligned multi-wall CNT patterned array grown at UC

7 Top of Tower Tower of Nanotubes Side of Tower (High Resolution)

8 Aligned multi-wall CNT patterned arrays grown at UC

9 4mm Longest Carbon Nanotube Array Grown at UC (a) UC Institute for Nanoscale Science and Technology

10 CNT Arrays based on NC A&T Substrates Array Flower

11 Why Does Nanotube Growth Stop?

12 Structural Reinforcement, Active Structures, Thermal and Fluids Applications UC Institute for Nanoscale Science and Technology

13 UC MULTIFUNCTIONAL NANOSKIN MWCNT Array Optional SWCNT Filler Paint Polymer, ceramic, or powdered metal filler Lightning discharge through skin and electrode Electrode Adhesive Structure Surface A Nanoskin is formed by embedding a conductive polymer into the arrays to stabilize the nanotubes and provide ion exchange

14 Nanoskin Tiles

15 Nanoskin as-grown ESEM images of MWCNT samples grown with Fe/Al2O3/SiO2/Si with low magnification, x 100 (scale bar is 200 micron). Growth condition: 500 SCCM of H2, 700 SCCM of C2H4, and 30 minutes.

16 Estimated elastic modulus of MWCNT-Epoxy nanoskin Elastic Modulus (GPa) Volume Fraction Limit for Processing Powdered Nanotubes MWCNT Array Nanocomposite MWCNT Powder Nanocomposite Nanotube Volume Fraction The elastic modulus of the array nanocomposite is will be much greater than the powder nanocomposite

17 Nanotubes to Reinforce Composites Boeing figures Adhesive Applications for the Nanoskin

18 Need for Electrical Conductivity in Aircraft Low Wear Nanoskin Tire UC Institute for Nanoscale Science and Technology

19 Actuation Applications of Carbon Nanotubes Nanotube actuator film Concept Aircraft with wings that twist

20 Electrochemical CNT Array Actuator in Electrolyte Nanotube Array Post 4 mm long Conductive Epoxy CNT Array Tower Grown at UC Setup for Actuation Experiment (a) 0.5 Hz (b) 5 Hz (c)

21 Super-capillarity Copyright 2005 Nanoworld Laboratory of nanotube Reproduction Prohibitedarrays Wet Dry Heat Management is a tremendous problem for ultra-high density IC s (Business Week, April 18, 2005, p. 90) Sisubstrate VLSI Electronic devices CNT array Hostmaterial H eatflow

22 Images of water Copyright 2005 on Nanoworld as-grown Laboratory Reproduction nanotube Prohibited array (Super-hydrophobocity) 0 Degrees (Flat surface) 45 Degrees 90 Degrees 180 Degrees

23 Structural Health Monitoring UC Institute for Nanoscale Science and Technology

24 A BIOMIMETIC STRUCTURAL NEURAL SYSTEM Carbon Nanotube Film Neurons Detects Cracking, Corrosion, Heat, Pressure, Chemicals

25 Design of a Carbon Nanotube Neuron r 4 r 3 r 2 r 1 case1 case 2 case 3 r 2 C 3 case 4 case 5 Neural System and crack propagation C 1 C 2 C 3 C 4 Spray-on neuron under development

26 MODELING NANOTUBE SENSING: STRAIN & CORROSION Z( ω) = R s + R p 1 + λ R 2ω jr 2 2 p pλ Cd λ 2ω Experimental Electrochemical Impedance Spectra (0.5Hz to 10KHz) and electrical model Increasing frequency The CNT is a strain sensor (piezoresistive effect) and a highly sensitive corrosion sensor (electrical impedance effect)

27 Conclusions UC Institute for Nanoscale Science and Technology

28 There are Unprecedented Opportunities for Structural NanoScience

29 Very Important: Teaching Nanotechnology LED BY THE UC INSTITUTE FOR NANOSCALE SCIENCE AND TECHNOLOGY Tom Mantei, Interim Director UC is ranked the # 2 US university in nano education; Small Times magazine s May/June issue, 2005 A New Nanotechnology Interdisciplinary 3 course sequence is planned