Low Cost Carbon Fiber and Novel Resin Systems for Marine and Hydrokinetic Composite Structures

Presenter: Dayakar PenumaduInstitute for Advanced Composites Manufacturing Innovation (IACMI) &

University of Tennessee, Knoxville (UTK)Tennessee, USA

dpenumad@utk.edu1-865-974-7708

International Symposium “Novel Composite Materials & Processes for Offshore Renewable Energy”

Friday 1st September 2017Cork, Ireland

“Novel Composite Materials and Processes for Offshore Renewable Energy” (MARINCOMP) (Grant no: 612531) is a European Commission, Marie Curie 7th Framework Programme funded Project, under the Industry Academia Partnerships and Pathways (IAPP) call: FP7-People-2013-IAPP.

The aims and objectives of the project are:

1. Aims to reduce the cost of offshore wind and tidal turbine blade structures2. To jointly develop and optimise carbon-fibre reinforced composite

materials which are tailored for long-term durability in the marine environment, and can be processed rapidly and cost-effectively3. New software tools such as a fatigue life design tool which

incorporates the effect of immersion in seawater, and a cost-performance model will be developed in the project4. Provide a step change in the use of carbon fibre in large high volume

composite structures

Source: http://www.marincomp.eu/

3

January 9, 2015: President Obama Announces New Composite Institute

“…and today, we’re proud to announce our latest manufacturing hub, and it is right here in Tennessee. Led by the University of Tennessee–Knoxville, the hub will be home to 122 public and private partners who are teaming up to develop materials that are lighter and stronger than steel. ”

4

Operated by an independent not-for-profit

Governed by a board of directors

A wholly owned subsidiary of the University of Tennessee Research Foundation

Incorporated in the State of Tennessee

Headquartered in Knoxville, Tennessee

$250M in funding with $70M from DOE and $180 from partners

What is IACMI?THE Composites Institute

5

National institute addressing critical challenges

Five/Ten Year Technical Goals:• 25/50% lower carbon fiber–reinforced polymer (CFRP) cost

• 50/75% reduction in CFRP embodied energy

• 80/95% composite recyclability into useful products

Clean energy ProductivityDomestic production capacityJob growth and economic development

Life cycle energy consumption

6

Technical Focus on Advanced Composites and Structures

Shared RD&D Facilities Support Industry

7

Solutionspinning

line Carbon Fiber Technology

Facility Pre-pregproduction

pilot/full scale

Pilot-scalePCM

1,000 ton press

Full ScalePCM

4,000 ton press

Scale-up Across IACMI State Partners

8

9

10

Recap on Carbon Fiber Composites(after Daniel & Ishai)

Materials and Length Scales

0

1000

2000

3000

4000

5000

6000

0 0.005 0.01 0.015 0.02

Tens

ile S

tres

s (M

Pa)

0

50

100

150

200

250

300

350

400

0 0.005 0.01 0.015 0.02

Mod

ulus

(GPa

)

Tensile Strain

Single Carbon Fiber

24k carbon fiber tow

t = 1/16” Pultruded plate

Single Fiber

TowPultrusion

Composite Additive Manufacturing for Tuned Microstructure: ORNL(MDF)-UTK Research

Big Area Additive Manufacturing of CarbonFiber Based ABS Composite System

U.S. Wave Resource Available Along our Coasts total ~2,640 TWh/yr.

SAND2017-9281 C

Sandia National Laboratories is a multi-mission laboratory managed and operated by National Technology and Engineering Solutions of Sandia, LLC., a wholly owned subsidiary of Honeywell International, Inc., for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-NA0003525.

SAND2017-9281 C

Material Design Tools for Marine and Hydrokinetic Composite StructuresBernadette Hernandez-Sanchez, SNLBudi Gunawan, SNLDavid Miller, MSUGeorge Bonheyo, PNNLScott Hughes, NRELFrancisco Presuel-Moreno, FAU

Project Overview

Marine and Hydrokinetics Advanced Materials Program: support the MHK industry through applied research and guidance on Materials & Coatings to enable viability, lower the cost of energy (COE), and accelerate commercialization.

The Challenge: Proper structural/component materials and coatings are critical to reducing engineering barriers, COE, and commercialization time

Structure Design & Component: (LOADS! uncertainty in composite/design) Environmental Exposure Issues Cost (Manufacture, O&M, Reliability) Safety & Certification

Partners: Sandia National Laboratories (Lead): Materials Evaluation & Coatings Pacific Northwest National Laboratory: Biofouling & Environmental Exposure Montana State University: Composite Materials Evaluation & Development North Dakota State University: Antifouling Coatings & Biofouling Evaluation Brigham Young University: Antifouling Coatings

SAND2017-9281 C

Examples of Some MHK Designs Exploring Composite Materials (listed in alphabetical order)

17Ocean Renewable Power Company Resolute Marine Energy

Lockheed Martin-OTEC Cold Water Pipe

All Photos Obtained From Company Websites and Literature References

Verdant Power

Columbia Power TechnologiesAquaHarmonics

SAND2017-9281 C

MHK Composite Workshop

18

• Worked with MHK community, supply chain, composite/coatings manufactures, U.S. Navy, Oil & Gas, and Marine Industries to understand needs and available resources to support MHK stakeholders. Results Presented at the 2016 Marine Energy Technology Symposium.

SAND2017-9281 C

MHK Composites Barriers & NeedsTop Barriers Identified to Using Composites for MHK include: Uncertainty in materials properties and selection for component (Short-Mid Term).

Industry wants to know if composites are the right materials to invest in? Why? Uncertainty in design with limited design tools & methodologies available (Mid-Long Term). Composites reliability and maintenance (inspection, repair) is not well understood (Mid-Long Term). Limited guidance on composites manufacture and assembly available to MHK developers (Long

Term). Weight and transportation issues affect current designs and manufacture (Long Term). Materials cost will affect final design ($/lb) (Long Term).

Top Composite Research Needs include: Reduce uncertainty of materials selection by evaluating performance properties of coupons and

substructure in artificial and actual saltwater environments (Short-Long Term). Evaluate MHK environmental effects on joints, seals, and fasteners of dissimilar materials in order to

facilitate complex geometries and modularity (Mid to long term). Test component at full-scale structures to facilitate design optimization (Mid-Long Term). Identify failure mechanisms and damage tolerances (Short-Long Term). Determine the influence of the manufacturing process on the structural performance (Mid-Long

Term). Determine what standards and certification process are needed for new materials to be employed

in the MHK energy industry (Long Term). 19

Short 1-5 (yrs).Mid 5-10 Long 10-20

SAND2017-9281 C

Database can be found in 2 locations online and is free for users to download.

20

http://energy.sandia.gov/energy/renewable-energy/water-power/technology-development/advanced-materials/mhk-materials-database/

• Both the wind and water icons take you to webpages that house the link.

• Under Water Power Database and Tools

SAND2017-9281 C

Environmental Composite Performance Testing at MSU

21

Couponsto

Structural elements

Elements to

Substructure

Testing to

Dissemination

Three different conditions are of interest:1. Dry State2. Artificial Sea Water (partial to full saturation)3. Actual Sea Water (partial to full saturation)

*soaked in tanks at PNNL (FY17-18)

Past efforts have indicated decrease in performance due to water uptake

SAND2017-9281 C

Evaluating Biofouling on Composite & CoatingPerformance at PNNL

22

Evaluate under static & flow conditions with unfiltered natural seawater.

Two Tanks will be used:1. Flow2. StaticShort Term Testing at 3 months

PNNL Marine Sciences Laboratory in Sequim , WA Flow Static

Examples of Tailor Made Coatings Testing at PNNL.

Currently Testing Composites and Coatings for Industry

SAND2017-9281 C

Developing Substructure Testing at NREL & MSU for FY18-19

23

Developing test plan to examine joints, plys, …..and other elements of design Three different conditions are also of interest:1. Dry State2. Artificial Sea Water (partial to full

saturation)3. Actual Sea Water (partial to full

saturation)

Test Frame at MSU

• Full-scale and component testing• Characterization, strength, and fatigue test

capabilities• 500 kN actuators, reaction stands to 17 MNm• Extensive structural measurement equipment

and condition monitoring systems

SAND2017-9281 C

Science Framework Utilized for Durability• Response of fibers, tows, resin, core material interfaces

to harsh naval environment• Response of fiber reinforced composite facings to multi-

axial static loading (tensile, compressive, torsional, combination involving principal stress rotation)

• Behavior under fatigue loading (tension-tension in this study) while the samples (composite facings and sandwich materials) allowed to have access to sea water

• Delamination behavior between facings and core materials

• Coupled effects of sea water and temperature• Utilization of high resolution computed tomography and

surface 3D DIC to relate process-property-environment effects.

Equi-bi-directional carbon fiber fabric/vinyl ester LT650 supplied by DevoldToray T700 12k towVE sizing Dow Derakane 510A-40, VE

VARTM process

Composite Material System Considered

CF/VE Facing

CF/VE with H100 Core

VARTM Set-up

Intact PVC H-100 foam and sea-water induced damage, sea water penetrates only to outer few cells where damage/degradation is highly localized

US Navy RelevanceMarine composites are exposed to sea water environment and temperature fluctuations over extended periods. The integrity of sandwich structures and configurational distortions subjected to the aforementioned exposures plays a significant role in their incorporation within naval designs and needs to be evaluated. Extreme loading condition of interests to Navy:• Sea water• Temperature range -50 ºC to 75 ºC• Water confinement• Coupling effects of l temp and sea

water, hydrostatic pressure / stress σo σo

L LCL

Hh

h

E

E

G

1

3

2 x

Sea Water induced expansionon Facing (layer 3) causes configurational distortions

Broad Classification from Sea Water UptakeSchematic curves representing a solid line, designated by LF, corresponds to linear Fickian diffusion and four possible categories of non-fickian weight-gain sorption data.• LF- Linear Fickian• “A” and “B” are typical variations corresponding to both neat polymers and fiber reinforced

composites• B represents the circumstance of two-stage diffusion• “C” accounts for the case of rapidly increasing fluid content. “D” accords with weight loss that is

attributable to chemical or physical break-down, both types not good for marine applications

VARTM-CFVE weight gain data for sea, distilled, and tap water.

• Pre-condition• Prepare specimens• Density of sea water 1.022 g/mL• Immersing in sea water at 40 ºC at least 3

months

Anisotropy of Moisture Induced Expansion Coefficient

Sample Conditions Average coefficient of moisture expansion

(µε/1% weight gain)

[0/90]2S 340

[15/75]2S 730

[30/60]2S 760

[±45]2S 1020

29

Degradation Effect on Fatigue Behavior

100 mm gage length

extensometer was used

to record strain data.

• Frequency of 1 HZ

• σ max/σ min = 0.2

• 0.60, 0.67, 0.80 of failue

stress/strength considered in

this study.

Comparison of type of confinement

• When fatigued with condition of water confinement, fatigue life was reduced by up to 50% of loading cycles compared to sample in air.

At least 3 of [±45]2S CF/VE samples in each case were utilized for a

fatigue life diagram for: (a) dry coupons fatigued in air, (b) dry coupons

fatigue while confined, and (c) dry coupon fatigue while only one-sided

confined.

• Confined effect: Internal water pressure rapidly increasing due to incompressibility during the downloading stage of the fatigue cycle

Fatigue in air

Fatigue with water confinement

Mechanical testing coupled with 3D DIC

Black on white speckle on surface sample. Subset between 33-35 pixel was used to track the strain from image to image.

Damage evolution in fiber dominated CFVE at 200, 500, 800, 1000 MPa

Why does damage localization occur in these bands and how doesLong-term and coupled sea water exposure exacerbate this observation?

Sea water exposure effects on damage evolution matrix dominated CF/VE subjected to 10 tensile load-

unload cycles

Compression Behavior

100 kN Actuator Displacement Rate of 1.3 mm/min

VIC-3D Cameras

VIC-3D Lights

Combined Loading and Compression Test Fixture

Speckle Pattern Compression Sample

37

38

Degree Orientation

Compression Modulus (GPa)

Failure Stress (MPa)

Compression Strength

(% Reduction)Dry Wet Dry Wet

0 41.0 64.1 461189

-49.2 to -59.057.1 234

4513.4 10.6 125 105

-12.4 to -18.410.3 102

10.3 11.2 129 10411.1 113

90

44.0 40.8 429 229

-26.4 to -50.146.1 63.1 431 33148.6 49.1 450 214N/A 48.3 N/A 262

Effect of Compression Behavior

Compression - orthogonal view xz

xz plane

x

Dry 45 degree fiber orientation CFVE approximately 0.63 cm beneath surface

Wet 45 degree fiber orientation CFVE approximately 0.67 cm beneath surface

2.33 cm

2.33 cm

Neutron tomographic reconstructions of dry and wet specimen

a) dry S1 b) dry S4 d) wet S4 c) wet S1

Concluding Remarks• Effects of degradation associated with long-term exposure to sea water and harsh

marine conditions on carbon fiber vinyl ester based composites and H100 PVC polymeric foam based sandwich structures was evaluated, compression behavior is strongly affected.

• For sandwich structures, important considerations in implementing composites for design should consider degradation associated with critical energy release rate corresponding to the delamination of facing with foam core material, a reduction of 30% was observed for CF/VE system manufactured using VARTM.

• Fatigue life for biaxial carbon fiber fabric based composites show substantial effect of sea water confinement on reduction in number of cycles to failure for tension-tension fatigue. A stress ratio of 0.55 can be considered for safe design, considering the anisotropy.

• Shape distortions due to moisture induced expansion from one-sided exposure can be estimated using a shear lag model, based on laboratory data corresponding to moisture uptake and related strain measurements.

• 3D DIC technique revealed occurrence of strain localizations and damage concentration zones and high resolution radiation based tomography using both x-rays and neutrons showed important differences resulting in the microstructure from marine environmental exposure conditions. Laboratory tests are representative of larger size panels for the considered material and manufacturing system.