Sayir - Aerospace Materials for Extreme Environments - Spring Reivew 2012

1 DISTRIBUTION A: Approved for public release; distribution is unlimited. 9 March 2012

Integrity Service Excellence

Dr. Ali Sayir

Program Manager

AFOSR/RSA

Air Force Research Laboratory

AEROSPACE MATERIALS

FOR EXTREME

ENVIRONMENTS

8 MAR 2012

2 DISTRIBUTION A: Approved for public release; distribution is unlimited.

2012 AFOSR SPRING REVIEW

NAME: AEROSPACE MATERIALS FOR EXTREME ENVIRONMENTS

BRIEF DESCRIPTION OF PORTFOLIO:

To provide the fundamental knowledge required to enable revolutionary

advances in future Air Force technologies through the discovery and

characterization of materials that can withstand extreme environments

(combined loads of mechanical-, thermal-, and other electromagnetic fields).

LIST SUB-AREAS IN PORTFOLIO:

• Theoretical and computational tools that aid in the discovery of new materials. • Ceramics

• Metals

• Hybrids (including composites)

• Mathematics to quantify the microstructure.

• Physics and chemistry of materials in highly stressed environments

• Experimental and computational tools to address the complexity of combined

external fields at extreme environments.


OUTLINE

I. Physics and chemistry of materials in highly stressed

environments.

II. Theoretical and/or computational tools that aid in the

discovery of new materials for hypersonic application.

III. Informatics and combinatorial based materials

discovery

IV. Challenges, Motivations and New initiatives.


High Temperature Phase Transformations in

Oxide Ceramics W. Kriven / UIUC


To study the ferroelastic phase transformation in

select rare-earth niobates (Y, La, and Dy) using in-

situ methods for possible applications in shape

memory ceramics

I. Monoclinic-to-tetragonal phase transformation in

LaNbO4, YNbO4 and DyNbO4 is second order

II. Transformation temperatures:

– LaNbO4 = 503º ± 18ºC

– YNbO4 = 867º ± 16ºC

– DyNbO4 = 875º ± 2ºC.

I. Room temperature spontaneous strain (es)

– LaNbO4 = 6.84%

– YNbO4 = 6.33%

– DyNbO4 = 6.48%

RNbO4 Phase Transformations

W. Kriven / UIUC

Z

X

Y

aT

cM

bM

aM

cT

bT

M

Monoclinic

Tetragonal

Z

X

Y

aT

cM

bM

aM

cT

bT

M

Z

X

Y

aT

cM

bM

aM

cT

bT

M

Monoclinic

Tetragonal

This is a second order

transformation having a

lattice correspondence on

transformation

am ↔ bt

bm ↔ ct

cm ↔ at


Distribution C: Distribution authorized to U.S. Government agencies and their contractors. To protect draft, planning, or other preliminary

information from premature dissemination. Other requests for this document shall be referred to AFOSR/PI.

Accomplishments

• Multiscale experimental perspective of plastic deformation

• Measurement of dislocation cell structures with SEM rather than a TEM

• Measured distribution and evolution of characteristic length scales of plastic deformation

Objective

• High spatial resolution experimental measurements of state variables that govern evolution of elastic-plastic deformation at high temperatures

Technical Approach

Two-dimensional indentation

– Metals (Ni, Ta) & Ceramics (monazite)

– Net Burgers Vector Density

– Nye dislocation tensor components

– Lower bound on Geometrically Necessary Dislocation (GND) density

Multi-scale experiments

– Spatial resolutions of 3 mm, 500 nm and 50 nm in overlapping regions

Multi-scale models

– Evolution of crystalline defects across length scales

Multiscale

Measurement of Lattice

Rotation

Relevance

• Will serve to inform and to validates physics-based constitutive models

Technology Transition

• Research collaborations – Lawrence Livermore National

Laboratory

– Brent Adams (BYU)

Cell size vs. GNDs 3 mm

Monazite

Crystal

Growth

Monazite

Micro-pillar

Tests

Measured Dislocation

Cell Structure with SW.

Plasticity in Extreme Environment:

Tantalum and Monazite J. W. Kysar / Columbia University


OUTLINE


environments.




discovery



UC Berkeley/ALS

R. Ritchie (mechanics, imaging) Combine experiments and

multi-scale models into a

virtual test system

multi-scale models

new experimental methods

new materials &

processing science

Teledyne Scientific

D. Marshall (materials & structures)B. Cox (mechanics of materials)

UC Santa Barbara F. Zok (structural materials)

R. McMeeking (mechanics)

M. Begley (mechanics)

U. of Texas

P. Kroll (atomistics)

Missouri University W. Fahrenholtz &G. Hilmas

(UHTCs)

U. of Colorado R. Raj (high temp.

materials &

properties)

U. of Miami

Q. Yang (mechanics)

Collaborations, test and

advisory support AFRL/WPAFB (M. Cinibulk)

NASA, Boeing, ATK, Lockheed-Martin International affiliate University of Canterbury

(S. Krumdieck)

Other collaborations von Karman Institute,

J. Marschall, SRI, U. Vermont

Gerhard Dehm, Leoben, Austria

M. Spearing,Univ. Southampton

Stepan Lomov, Kath. Univ. Leuven

Loughborough Univ. (UK)

M. Smart Univ. Queensland

National Hypersonic Science Center for

Materials and Structures


10 mm HfO2

reinfiltrated Hf-PDC

in shrinkage crack

Hf-PDC

GB phase

rigid scaffold

rigid network of

large particles

Multilayer

HfO2/PDC

CVD

SiC

fiber

tow

Some Target Microstructures D. Marshall & B. Cox (Teledyne) / Zok (UCSB) & R. McKeeing & M. Begley/ Q. Yang (U. Miami) / W.

Fahrenholtz &G. Hilmas (UMR) / R. Raj (U. Colorado) / R. Ritchie (UC Berkeley) / P. Kroll (U. Texas)

National Hypersonic Science Center

HfO2

Hf-PDC

HfO2

1 mm 0.1 mm

1 mm

10 DISTRIBUTION A: Approved for public release; distribution is unlimited. Distribution C: Distribution authorized to U.S. Government agencies and their contractors. To protect draft, planning, or other preliminary


Synchrotron Imaging of Structure and Damage

R. Ritchie (UC Berkeley) / National Hypersonic Science Center

Compound visualization of statistical parameters

5mm

Compound visualization of statistical parameters

5mm

Tow cross

sectional

area

3-D microstructural

characterization &

geometry generator

8 8 octopoleoctopole 1000W1000W

IR lamps IR lamps

XX--raysrays

dogdog--bonebone

sample sample

water water

coolingcooling

and sample and sample

mount accessmount access

360 deg 360 deg

thin windowthin window

0.25 mm Al 0.25 mm Al

Lamp

Lamp

Lamp

Lamp

Lamp

to load cell and water cooling to load cell and water cooling

guidewayguideway

motor andmotor and

gearboxgearbox

X-rays

load cell load cell

furnace furnace

section section

with with

active active

cooling cooling

OctopoleOctopole IR lamp IR lamp

arrangement arrangement

water water

coolingcooling

LBNL design : LBNL design : J.NasiatkaJ.Nasiatka, , A.MacDowellA.MacDowell

8 8 octopoleoctopole 1000W1000W

IR lamps IR lamps

XX--raysrays

dogdog--bonebone

sample sample

water water

coolingcooling

and sample and sample

mount accessmount access

360 deg 360 deg

thin windowthin window

0.25 mm Al 0.25 mm Al

Lamp

Lamp

Lamp

Lamp

Lamp

to load cell and water cooling to load cell and water cooling

guidewayguideway

motor andmotor and

gearboxgearbox

X-rays

load cell load cell

furnace furnace

section section

with with

active active

cooling cooling

OctopoleOctopole IR lamp IR lamp

arrangement arrangement

water water

coolingcooling

LBNL design : LBNL design : J.NasiatkaJ.Nasiatka, , A.MacDowellA.MacDowell

crack

2D 2D tomographictomographic slices with no loadslices with no load

SiC-SiC composite: RT in situ loading

High temperature in situ stage (1500 oC)

Resolution < 1mm

Input to constitutive law

calibration in virtual test



Pipeline Exercise (3D) R. Ritchie (UC Berkeley) / B. Cox (Teledyne) / Zok (UCSB) / Yang (U.

Miami) / D. Marshall (Teledyne) / National Hypersonic Science Center

3D geometric model

(UCSB & Teledyne)

2D cross-section data (UCSB & Teledyne)

mCT data from UC-Berkeley - Ritchie

3D FEM -0.005

0

0.005

0.01

0.015

0.02

0.025

0 1 2 3 4 5 6 7 8 9 10

Simulated surface strain

(UM – Yang)

Validation from Measured surface strain

(UCSB – Zok)


Amorphous Ceramics

Hf-Si-C-N-O Si-C-O with “free” C

• grain boundary phases (Hf/Zr-Si-C-O)

• models for melts (W-Si-B-O)

• synthesized “hierarchical” materials

(PDC or CVD)

T

time

1000

2000

3000

4000

5000

120 ps 90 ps 60 ps 30 ps

• network approach (modified WWW algorithm)

• melt-quench

• DFT, ab initio molecular dynamics (VASP-code)

• both approaches augmented with repeated annealing to achieve low-

energy structures

Disordered Structures

P. Kroll (U. Texas) / National Hypersonic Science Center


Structure Models : Hf-Si-C-O

P. Kroll (U. Texas) / National Hypersonic Science Center

Example: Hf-Si-C-O : 20 HfO2 + 15 SiO2 + 5 SiC + 5 C

or 15 HfSiO4 + 5 HfO2 + 5 SiC + 5 C

Si-C substructure

(sideview)

• DE in SiCO larger

than DE in SiO2 • Barrier 1 – 3 eV

SiCO glass, Si52C12O80,

25mol%SiC

Diffusion of O2 in SiCO glass is smaller

than in SiO2 (if void structure is similar )


Collection optics are f/4 –

and aperture is ~ 1mm for

30 kW ICP

•Pulse energy ≤ 0.25 mJ

with a 0.5 mm beam

diameter to avoid

complications such as

multi-photon ionization

Objective: Translate collection optics and beam

to measure temperature and species distributions

Laser Diagnostics: Property Gradients

D. Fletcher / U. Vermont

ni(x)

T(x)

Flow

Interface

Gas Phase

Boundary


Computational estimates of

critical content – feasibility

assessment and define

experimental window. (Models used – An extended Miedema

model (semi-empirical thermodynamics)

and ab-initio calculations using VASP,

with GGA potentials )

Use computational results,

basic thermodynamics and

experimental results for

analyzing the system. (Density of states calculations from

VASP, interface enthalpy values from

Miedema for understanding stability

and partitioning)

SEM of a Mo60W15Si25 two phase

alloy (Mo,W) ss and (Mo,W)5Si3.

0 50 100 150 200 250 300 350

1100

1300

1500

1700

BO2 = 518.8 nm

B

RA

W S

IGN

AL,

a.u

.

= 249.9 nm

TEST TIME, s

TE

MP

ER

AT

UR

E, °C

BOINT

EN

SIT

Y,

a.u

.

= 404.1 nm

Biasing Reactions of Mo-Si-B-Alloys D. Fletcher (U. Vermont) / J. Prepezko (U. Wisconsin) /

M. Akinc (u. Iowa) / J. Marshall (SRI Int.)

T2

BCC A15 T1

Mo2B

MoB



An aqueous, non-toxic

method for electroplating

Re-Me coatings

Me0

Cu

substrate

Me2+

Ni2+ + 2 e-M Ni0M

Ni0M + ReO4- + 2H+ Ni2+

M + ReO3- + H2O

Cu

substrate

Me0

Me2+

Re0

ReO4-

ReO3-

2e-

ReO3- + 5e-

M + 3H2O Re0M + 6(OH)-

100 µm(a)

100 µm(b)

100 µm(c)

100 µm(a) 100 µm(a)

100 µm(b) 100 µm(b)

100 µm(c) 100 µm(c)

100 µm(a)

100 µm(b)

100 µm(c)

100 µm(a) 100 µm(a)

100 µm(b) 100 µm(b)

100 µm(c) 100 µm(c)

100 µm(a)

100 µm(b)

100 µm(c)

100 µm(a) 100 µm(a)

100 µm(b) 100 µm(b)

100 µm(c) 100 µm(c)

Objective:

•Understand the mechanism that governs the

electrodeposition of Re and its alloys.

Re-Co Re-Fe Re-Ni

Electroplating Rhenium and its Alloys S.R. Taylor / U. Texas Health Science &

N. Eliaz / Tel Aviv University, ISRAEL

Calculations (NSF):

• Binding Energies:

Ni-Cu and Re-Cu

• Transition State

(Potential Barrier)

• Reduction Potential (Ni(II) &

Re(VII)) vs Ag/AgCl)

• Entropy: Ni-Cu and Re-Cu


OUTLINE


environments.




discovery



Crystal

Structure Crystal

Chemistry

Property

Dielectric loss

TC

PS

d33

Ionic Size

Polarizability

Tetragonality

Bond covalency

Ionic displacement

High-dimensional descriptor space

PCA

Rough sets

❖Ionic size

❖Pseudopotential radii

❖Bond length

❖Pauling

❖electronegativity

❖Polarizing power

❖Mendeleev number

Six key factors affecting TC of

BiMeO3-PbTiO3 ferroelectrics

We started with 48 descriptors

and down-selected them to 6

48 potential

descriptors

Data Mining

Statistical Learning

Ranking and

identification of key

factors that govern

TC

Informatics and Combinatorial Based Discovery

K. Rajan / U. Iowa



Nano-calorimeter array

Cooling rate (K/s)

High Temperature Combinatorial Nano-

Calorimetry for Materials Discovery J. Vlassak / Harvard U.


OUTLINE


environments.




discovery



OLD: • Photography is over 150 years old

• Photochromics are on stage several decades

• Photolithography, electron lithography, and ablation

are standard tools.

• Photosynthesis is nearly as old as life.

NEW:

Ability to increase materials excitation in

a controlled way (i.e., lasers and other EM).

CHALLENGES: (Conceptual framework between experiments and theory)

I. Energy localization (ionic or electronic); Electronic excited states (Non- Equilibrium).

II. Charge Localization (It does guide the energy localization): femtosecond to years.

III. The link between microscopic (atomistic) and mesoscopic (microstructural) scales.

Energy transfer (i.e., displacements do not need to occur at the site originally excited;

Photosynthesis - NOT FULLY UNDERSTOOD).

IV. Energy storage (energy sinks can delay damage and the process characteristics).

V. Charge transfer and space charge.

CHALLENGE I: PROCESSING SCIENCE

Electromagnetic Excitation is a Means to Change Materials Properties


CHALLENGE II:

Design: GB Phase Diagrams

• Fabrication protocols utilizing

appropriate GB structures to achieve

optimal microstructures

• Co-doping strategies and/or heat

treatment recipes to tune the GB

structures for desired performance

Understanding of Non-Equilibrium Structures at different Length Scales

J. Luo / Clemson U.

Discrete Thickness

1 nm

Ni-Bi

1 nm

Ni-Bi

Luo, Cheng, Asl, Kiely & Harmer, Science 333: 1730 (2011)

Nanometer “Equilibrium” Thickness

2 nm 2 nm

Mo-Ni W-Ni

Luo, Cheng, Asl, &, Kiely, In Preparation (2012)


Two Questions:

1) Finite Atomic Size?

2) A Series of Discrete Grain Boundary Phases?

CHALLENGE II:

Quantitative Descriptors for the Interface

ONR MURI 2011 (Dr. Dave Shifler):

Atomic-Scale Interphase: Exploring New Material States

AFOSR MURI 2012

(Drs. F. Fahroo and A. Sayir):

Information Complexity in

Predictive Material Science

• Structure description

• Uncertainty quantification

• Cross-Entropy minimization

• Info complexity Management • Machine learning

Definition of local state ?: •Composition / activity •Lattice orientation •External field coupling •Energy


Unsolved Problem I:

Surface temperature history

The von Karman Institute 1.2 MW Plasmatron

Induct. heat: 1.2 MW (max)

Enthalpy: 10 – 50 MJ kg-1 (for air)

Ma range: < 0.3

qstag: 10 – 300 W cm-2

Pstag : 0.05 – 0.15 atm

0 60 120 180 240 300 360 420 480 540 600 6601200

1400

1600

1800

2000

2200

2400

2600

2800

SU

RF

AC

E T

EM

PE

RA

TU

RE

, K

TEST TIME, s

3.3

3.5

3.9

3.4

3.2

ZrB2-30vol%SiC-4mol%WC

1000

1200

1400

1600

1800

2000

2200

2400

2600

Mass flow: 16 g/s

Pchamber

: 10 kPa

Spontaneous

Temperature

Jump

~470 K

SU

RF

AC

E T

EM

PE

RA

TU

RE

, °C

Plasmatron Power Increase

Dqcw

= 40-80 W/cm2

qcw

=75-85 W/cm2

Wall

Ions, Neutral Gas, Plasma

Electrons, and Radiation

Ions, Neutral Gas, Plasma

Electrons, Secondary Electrons,

Wall Material, and Radiation

Conductive Heat Loss

Sheath formation affects both the plasma and the wall I) Ions strikes: • Sputter wall material and ejects species into plasma • Neutralization pulls electrons from the wall • SEE that cools the plasma & deposit plasma energy into wall II) Electrons strikes: • SEE and deposit energy • Impact atomic structure of wall

CHALLENGE III:

Materials Far From Equilibrium

De Gris et al., 2010

470 K Temperature Jump !

Unsolved Problem II:

Instability and 3D Erosion

AFOSR BRI 2011: Materials far from Equilibrium (Drs. M. Birkan, J. Luginsland, and A. Sayir)

Wall’s Contribution must be considered !

J. Marshall / SRI


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