Inherently Adaptive Structural Materials

Technova Corporation

Outline of the Presentation

Structural and Adaptive Qualities of BoneBiomimetic Principles of Adaptive MaterialsDesign & Evaluation of Integrated Adaptive SystemsProcessing of NanocompositesModeling and Validation of Structural Principles

Development of Bone Structure

Cancellous Bone Compact Bone

Mechanisms of Bone AdaptationLoads Build of Bone

Strains

Comparison Signal

Remodeling

Electrical Potential Gradient Under Bending Bone Remodeling Under Bending

Consequences of Bone Adaptation

Arrangement of Struts Along Principal Strain Lines

Optimization of Topology

Outline of the Presentation

Structural and Adaptive Qualities of Bone

Biomimetic Principles of Adaptive Materials

Design & Evaluation of Integrated Adaptive Systems

Processing of Nanocomposites

Modeling and Validation of Structural Principles

Key Constituents and Processes

Piezoelectricity

Electrolysis

Solid Electrolytes

+ + + + + + + + +- - - - - - - - - +

++

+

--

--

V = g.s.tQ = d.s.A

V = Vo + i.R + VeQ = n.F

Experimental Validation of Electrolysis Through Solid Electrolyte

Electrolytic Cell

-50 -40 -30 -20 -10 0 10 20 30 40 50Voltage, mV

-1.00

-0.75

-0.50

-0.25

0.00

0.25

0.50

0.75

1.00

Cur

ren t

, mA

Voltammogram Micrographs

Design & Validation of Piezo-Driven Electrolysis

+ + + + + + +- - - - - - - Stainless Steel Mesh

Copper-Ion Conduct ing PolymerCopper Layer

Piezoelectric Stack

Applied Stress:

Stress, MPa

Time, sec

30

1

Outline of the Presentation

Structural and Adaptive Qualities of BoneBiomimetic Principles of Adaptive MaterialsDesign & Evaluation of Integrated Adaptive SystemsProcessing of NanocompositesModeling and Validation of Structural Principles

Designs and Validation of a Basic SystemReplicated Multilayers of: Insulative Lay Conductive Layer (Tc) Piezoelectric Layer (Tp) Solid Electrolyte Layer (Ts) Metallic Layer (Tm)

T

L

W

W1

L1

Schematic Presentation

V = g33.s.Tp

Q = d33.s.(n.L1.W1)

er (Ti)

Processing and Test Set-Ups

System Ti Tc Tp Ts Tm

I (conventional) 50 µm 50 µm 50 µm 50 µm 50 µm

II (nanocomposite) 5 nm 5 nm 50 nm 40 nm 40 nm

Alternative Designs

An Elaborate Adaptive Element

A A

Section A-A

Nanolayered CompositeComprising Replicated:

Insulative Nanolayer (Ti)Conductive Nanolayer (Tc)Piezoelectric Nanolayer (Tp)Solid Electrolyte Nanoayer (Ts)Metallic Nanoayer (Tm)

(a) (b) (c)

e

e

Mass Transfer

(d)

e

e

(e)

+ +

+ +

- -

--

Mass Transfer

Detailed System Design and Analysis

A A

Section A-A

Nanolayered CompositeComprising Replicated:

Insulative Nanolayer (Ti = 5 nanometer)Conductive Nanolayer (Tc = 5 nanometer)Piezoelectric Nanolayer (Tp = 150 nanometer)Solid Electrolyte Nanoayer (Ts = 40 nanometer)Metallic Nanoayer (Tm = 150 nanometer)

10 mm

1 mm

1 m

(a) Concentric Loading (b) Eccentric Loading

e

e

(c) Concentricity Restored by Self-Adaptation

8.33 MPa 43 MPa-26 MPa

8.33 MPa

System Design

Structural & Adaptive Analysis

Preliminary Assessment of Structural Implications

Preliminary Assessment of Structural Implications

Outline of the Presentation

Structural and Adaptive Qualities of BoneBiomimetic Principles of Adaptive MaterialsDesign & Evaluation of Integrated Adaptive SystemsProcessing of NanocompositesModeling and Validation of Structural Principles

Ionic Self-Assembly: Basic Principles

Mechanism of Self-Assembly Build-Up of Nanolayers

Adaptation of Ionic Self-Assembly

Subst rate / PEI

PEI/[PSS/PAH]3

PEI/[PSS/PAH]3 Au]1

PEI/[PSS/PAH]3 Au/PAH]2

PEI/[PSS/PAH]3 Au/PAH]3

Substrate

PAH/PS119

PAh/PS119/ZrO2

Mult iple ZrO2/Polymer Layers

Manual and Automated Processing Self-Assembly of Colloidal Nanoparticles

Self-Assembly of Piezoelectric and Conducting Nanolayers

FElect rode

V

C0

Electrode

ITO-Coated Glass Substrate

Ionically Self-Assembled,Mult ilayer PSS/PDDA System

00.20.40.60.8

11.21.41.61.8

2

0 1 2 3 4 5 6 7

Applied Force, g

Out

put V

Olta

ge, m

V

Outline of the Presentation

Structural and Adaptive Qualities of BoneBiomimetic Principles of Adaptive MaterialsDesign & Evaluation of Integrated Adaptive SystemsProcessing of NanocompositeModeling and Validation of Structural Principles

Section-Level Structural Modeling

Modeling Principles

∫ ∫ =+c lA A llcc NdAfdAf

∫ ∫ =+c lA A llcc MydAfydAf

Effect of Hybrid Nanolayer Build-Up on RVC Section Behavior

Preliminary System-Level Analysis

(a) Bending (b) Buckling (c) Yielding (d) Fracture

Failure Modes

Effect of Multi-Layer Polymer/Ceramic/Metal Build-Upon Bulk Properties of RVC Open-Cell System

11Tensile Strength

21Elastic Modulus

3.9Density

Composite/Base RatioProperty

Preliminary Structural Evaluation

Open-Cell Structure and Tension Test Set-Up

Strain, mm/mm

Stre

ss, M

Pa

0.002 0.004 0.006 0.008 0.010 0.012 0.014 0.016

0.03

0.06

0.09

0.12

0.15

0.18

As-Received

After Deposition ofPolymeric Nanolayers

Effect of Polymer Nanolayers on Tensile Behavior of Open-Cell Structure

Summary & Conclusions

Selection of adaptive system constituents and viable architectures

Modeling, design and experimental validation of adaptive structures

Implementation of nanocomposite processing techniques

Modeling and validation of structural principles