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Materials and Processes DivisionESA/ESTEC/TOS-QM
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The ESA SME Initiative Training Courses
The Spacecraft Environment The Spacecraft Environment The Spacecraft Environment The Spacecraft Environment and Materials Interactionand Materials Interactionand Materials Interactionand Materials Interaction
Marc Van EesbeekHead Materials Physics and Chemistry Section
Materials and Processes DivisionESA/ESTEC/TEC-QM
TEC/QMC 2
The ESA SME Initiative Training Courses
Introduction
On-ground Environment
Launch Environment
Space Environment
Materials and Processes DivisionESA/ESTEC/TEC-QM
TEC/QMC 3
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On- Ground
Temperature
Humidity
Atmosphere
Biological
Transport loads
Test
Materials and Processes DivisionESA/ESTEC/TEC-QM
TEC/QMC 4
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Launch and Ascent
Vibrations
Accelerations
Shocks
Thermal flux
Lightening impact
Rain
Birds0
1
2
3
4
5
0 200 400 600 800 1000 1200
Time (s)
1/2 separation2/3 separation
Solid Boosters burn outLiquid Booster burn out
3rd stage Cut Off
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In Flight
e -, p +, X-ray, hνννν
Micrometeoroid
Cosmic raysDebris
temperatureVacuumRadiationSpace DebrisMicrometeoritesAtomic Oxygen
Materials and Processes DivisionESA/ESTEC/TEC-QM
TEC/QMC 6
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Materials and Processes DivisionESA/ESTEC/TEC-QM
TEC/QMC 7
The ESA SME Initiative Training Courses
Materials and Processes DivisionESA/ESTEC/TEC-QM
TEC/QMC 8
The ESA SME Initiative Training Courses
NUMEROUS PROBLEMSMAINLY DIMENSIONAL STABILITY
AND LUBRICATION
CHANGE IN OPERATIONALPROPERTIES OF
MATERIALS
OUTGASSINGVACUUM
GAS CLOUD
PERTURBATION OFMEASUREMENTS
NUMEROUS PROBLEMSESPECIALLY ON
SCIENTIFIC SATELLITES
CORONA
ARC
ELECTRICALPROBLEMS
CONDENSATION
MODIFICATION THERMO-OPTICAL
PROPERTIES
MODIFICATION RADIATIONEFFECTS
MODIFICATION ELECTRICALPROPERTIES
THERMALPROBLEMS
ELECTRICALPROBLEMS
( SEE “RADIATION”)
( SEE“TEMPERATURE”)
Space Environment Effects : Vacuum
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TEC/QMC 9
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Pressure as function of height
Altitude(Km)
Pressure(mbar)
KineticTemperature(K)
Gaseous Density(particles/cm3)
Composition
Sea Level 1013 ~300 2.5x1019 78%N2,21%O2,1%Ar
30 10 ~173 4x1017 N2,O2,Ar200 10-6 ~1200 1010 N2,O,O2,O+
800 10-9 ~1300 106 O,He,O+,H6500 10-13 103 H+,H,He+
22000 <10-13 101-102 85% H+, 15%He2+
Materials and Processes DivisionESA/ESTEC/TEC-QM
TEC/QMC 10
The ESA SME Initiative Training Courses
NUMEROUS PROBLEMSMAINLY DIMENSIONAL STABILITY
AND LUBRICATION
CHANGE IN OPERATIONALPROPERTIES OF
MATERIALS
OUTGASSINGVACUUM
GAS CLOUD
PERTURBATION OFMEASUREMENTS
NUMEROUS PROBLEMSESPECIALLY ON
SCIENTIFIC SATELLITES
CORONA
ARC
ELECTRICALPROBLEMS
CONDENSATION
MODIFICATION THERMO-OPTICAL
PROPERTIES
MODIFICATION RADIATIONEFFECTS
MODIFICATION ELECTRICALPROPERTIES
THERMALPROBLEMS
ELECTRICALPROBLEMS
( SEE “RADIATION”)
( SEE“TEMPERATURE”)
Space Environment Effects : Vacuum
Materials and Processes DivisionESA/ESTEC/TEC-QM
TEC/QMC 11
The ESA SME Initiative Training Courses
Materials and Processes DivisionESA/ESTEC/TEC-QM
TEC/QMC 12
The ESA SME Initiative Training Courses
Materials and Processes DivisionESA/ESTEC/TEC-QM
TEC/QMC 13
The ESA SME Initiative Training Courses
Materials and Processes DivisionESA/ESTEC/TEC-QM
TEC/QMC 14
The ESA SME Initiative Training Courses
Materials and Processes DivisionESA/ESTEC/TEC-QM
TEC/QMC 15
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Space Environment Effect : Radiation
NUMEROUS PROBLEMSPARTICULARLY ON
SCIENTIFIC SATELLITES
PERTURBATION OFMEASUREMENTS
MODIFICATION OF THE ELECTRICALCHARGE STATE/ SURFACE CHARGINGINCREASED
OUTGASSING
MODIFICATION ATMOLECULAR LEVEL
MODIFICATIONTHERMO-OPTICAL
PROPERTIES
THERMAL PROBLEMS
RADIATION(VV, PROTONS,ELECTRONS)
INCREASED SENSITIVITY
MODIFICATION MECHANICALPROPERTIES
BREAKDOWN ELECTRICALPROBLEMS
FRACTURES (THINSTRUCTURES UNDER
STRESS)
(SEE “VACUUM”)
( SEE “TEMPERATURE” )
( SEE “ATOX” )
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TEC/QMC 16
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High Energy Solar Flux
Type Wavelength(nm)
Average Flux(W/m2)
Worst CaseFlux (W/m2)
Near UV 180-400 118 177
UV <180 2.3x10-2 4.6x10-2
FUV 100-150 7.5x10-3 1.5x10-2
EUV 10-100 2x10-3 4x10-3
X-rays 1-10 5x10-5 1x10-4
Flare X-rays 0.1-1 1x10-4 1x10-3
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Particle Radiation
Orbit Fluence [J.m-2. Year-1] Absorbed Dose in 4 µm Al(Gy.year-1)
Electrons Protons Total Electrons Protons TotalMIR;LEO;350;
51,6;C4.6x102 11 4.7x102 6.4x102 1.5x101 6.6x102
ISS;LEO;426;51.6;C
8.6x102 36 9.0x102 1.2x103 4.8x101 1.2x103
GEO;35790;0;C
9.8x105 3.8x104 1x106 5.4x105 8.3x106 8.8x106
GLON;19100;64.9;C
8.3x105 2.6x105 1.1x106 3.8x105 2x106 2.4x106
HEO;500-39660;65;E
4.9x105 6.8x104 5.6x105 2.6x105 3.1x105 5.7x105
POL;LEO;600;97;C
2.3x103 1x102 2.4x103 2.5x103 3.0x102 2.8x103
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Charged Particles Environment
Radiation Source Nature Energy Flux(part.cm-2s-1)
Characteristics Remarks
Galactic CosmicRays
Protons (~90%)α(He-nucleus) &Heavy Ions (10%)
10-2 GeV-1010 GeV 2-5 Least Significant formaterials
Solar Wind Protons (96%)α and O-ionsElectrons
~ 1KeV~ 1 KeV~20-40 eV
p+ 2.108 at 1A.U. - Neutral plasma- Low energy restricts hazards
to surface
No influence oncircumterrestrial orbits ataltitudes<6.6 RE
Solar CosmicEvents (Flares)
Protons (95%)Heavy Ions
1-100 MeV(below 10 MeVspectrum ~E-1..2,beyond ~E-5)
Precise predictionof solar activitycannot be made
- E and N particles varies byevents
- Omnidirectional isotropic
Trapped Radiation1.Inner Belts (1.2-3.2 RE)
2.Outer Belts(3-7 RE)
Protons andelectrons
Protons andelectrons
Ep+ < 30 MeV (90%)Ee- < 5MeV (90%)
All Ep+<1MeV
p+ 5.105 E>1 MeVe- 2.107 E>.5MeV
p+ 109 E>10KeVe- 5.2.107 e-5xE
with E in MeV
- Omnidirectional Isotropic- Flux varies with magnetic
latitude- Spectra are very variable
with solar activity (GEO)- Fluxes not entirely
symmetric in Longitude(SAA for protons)
- Most important for orbitsat altitude <6.6 RE
- High E protons in innerbelts only- Atomic displacements arepossible at LEO in SAA
Aurora Electrons andprotons
e- 2KeV<E<20 KeVp+ 80<E<800 KeV
e- 1010 duringstormsp+ <107
- Observed between 65o and70o N and S magneticlatitude at altitudes between100 and 1000 km
- Very much time dependent
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Space Environment Effect : Radiation
NUMEROUS PROBLEMSPARTICULARLY ON
SCIENTIFIC SATELLITES
PERTURBATION OFMEASUREMENTS
MODIFICATION OF THE ELECTRICALCHARGE STATE/ SURFACE CHARGINGINCREASED
OUTGASSING
MODIFICATION ATMOLECULAR LEVEL
MODIFICATIONTHERMO-OPTICAL
PROPERTIES
THERMAL PROBLEMS
RADIATION(VV, PROTONS,ELECTRONS)
INCREASED SENSITIVITY
MODIFICATION MECHANICALPROPERTIES
BREAKDOWN ELECTRICALPROBLEMS
FRACTURES (THINSTRUCTURES UNDER
STRESS)
(SEE “VACUUM”)
( SEE “TEMPERATURE” )
( SEE “ATOX” )
Materials and Processes DivisionESA/ESTEC/TEC-QM
TEC/QMC 20
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White paints
Coating ααααs initial ∆α∆α∆α∆αs after 1100e.s.h.
∆α∆α∆α∆αs after 1100e.s.h. + e- +p+
PSB 0.135 0.025 0.20
SG120FD 0.2 0.042 0.145
PSBN 0.16 0.010 0.11
SG121FD 0.154 0.011 0.078
PCBE 0.23 0.003 0.063
PCBZ 0.19 0.03 0.17
Z93P 0.136 0.025 0.094
S13GP6N 0.20 0.021 0.193
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SSM and Flexible Solar Reflectors (RSF)
Material ααααs∆α∆α∆α∆αs after 1100
e.s.h. UV∆α∆α∆α∆αs after 1100
e.s.h. UV + e- +p+
RSF-R on Al 0.126 - 0.003 0.06
RSF-F on Al 0.132 -0.007 0.058
RSF-F C on Al 0.137 0.002 0.07
SSM FEP 125µµµµm /Ag 0.07 0.01 0.03
SSM FEP 25µµµµm 0.153 .025 0.04
MAPATOX K 0.42 0.009 0.026
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Effect contamination on Solar Absorption
Materials and Processes DivisionESA/ESTEC/TEC-QM
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Solar Absorptance in Flight Data
Materials and Processes DivisionESA/ESTEC/TEC-QM
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Effect of Radiation on Tensile strength of Mylar
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Radiation Sensitivity of Polymers
PTFE
FEPFilled Siloxanes
Unfilled Siloxanes
Polyimides
Nylon
Polyurethane
PolyethyleneMinor Noticeable Significant
Absorbed dose (Gy)105 106 107
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Space Environment Effects : Temperature
(SEE “VACUUM” )
INCREASED OUTGASSING
MOLECULARDEGRADATION
HIGH
CYCLING
LOW
INCREASEDCONDENSATION
TEMPERATURE
MODIFICATIONELECTRICAL PROPERTIES
MODIFICATIONMECHANICAL PROPERTIES
THERMALMECHANICAL
FATIGUE
DEGRADATION OF OPERATIONALPROPERTIES OF MATERIALS
DEBONDING
FRACTURES/CRACKS
LOSS OF PROTECTIVECOATING
MODIFICATION CHARGESTATE
( SEE “VACUUM”)
EMBRITTLEMENT
(SEE “ATOX”)
(SEE“RADIATIONS”)
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Equilibrium surface temperaturesMercury, Venus, Earth orbits
Surface Temperature (sun facing)
-1 00 .0 0
0 .0 0
1 00 .0 0
2 00 .0 0
3 00 .0 0
4 00 .0 0
5 00 .0 0
0 .05 0 .15 0 .2 5 0 .3 5 0 .4 5 0 .5 5 0 .6 5 0 .7 5 0 .85 0 .95
Alpha/Epsilon ratio
[deg
C]
T celsius 1AU T celsius 0.47 AU Mercury ap
T celsius 0.31 AU Mercury per T celsius 0.72 Venus
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Thermo-0ptical Properties of Coatings
0 0.2 0.4 0.6 0.8 1
Thermo optical comparison
MetalOSRFEPKaptonBlack PaintWhite Paint
0
0.2
0.4
0.6
0.8
1
εH
αs
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Space Environment Effects : Temperature
(SEE “VACUUM” )
INCREASED OUTGASSING
MOLECULARDEGRADATION
HIGH
CYCLING
LOW
INCREASEDCONDENSATION
TEMPERATURE
MODIFICATIONELECTRICAL PROPERTIES
MODIFICATIONMECHANICAL PROPERTIES
THERMALMECHANICAL
FATIGUE
DEGRADATION OF OPERATIONALPROPERTIES OF MATERIALS
DEBONDING
FRACTURES/CRACKS
LOSS OF PROTECTIVECOATING
MODIFICATION CHARGESTATE
( SEE “VACUUM”)
EMBRITTLEMENT
(SEE “ATOX”)
(SEE“RADIATIONS”)
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Nov 1995
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FEP/VDA Pristine
VDA layer at BOL
14 days aged at 200 °C 44.9 days aged at 200 °C TC –100 °C/+100 °C
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FEP/VDA 14 days at 200C
Materials and Processes DivisionESA/ESTEC/TEC-QM
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FEP/VDA 6400 cycles between –100/+100
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Materials and Processes DivisionESA/ESTEC/TEC-QM
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ATOMICOXYGEN(ATOX)
OXIDATION
OXIDE LAYER
BREAKAGE
EROSION
PROTECTION
CONTAMINATIONCLOUD
GENERATION OFPARTICLES
DEGRADATIONMECHANICALPROPERTIES
CHANGE INTHERMO-OPTICAL
PROPERTIES
MASS LOSS
TEXTURE CHANGE
ELIMINATION OFCONTAMINANTS
PROPERTYRECOVERY
RUPTURE/DEFORMATION
( SEE “TEMPERATURE” )
Space Environment Effects : Atomic Oxygen
Materials and Processes DivisionESA/ESTEC/TEC-QM
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Neutral Composition during Medium Solar Activity
1
100
104
106
108
1010
1012
1014
1016
1018
1020
200 400 600 800 1000
N /m3
km
Ar
02
N2
N
OHeH
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O- density
108
1010
1012
1014
1016
1018
1020
200 400 600 800 1000
O (N/m3)
km
High Solar Activity
Medium Solar Activity
Low Solar Activity
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ATOMICOXYGEN(ATOX)
OXIDATION
OXIDE LAYER
BREAKAGE
EROSION
PROTECTION
CONTAMINATIONCLOUD
GENERATION OFPARTICLES
DEGRADATIONMECHANICALPROPERTIES
CHANGE INTHERMO-OPTICAL
PROPERTIES
MASS LOSS
TEXTURE CHANGE
ELIMINATION OFCONTAMINANTS
PROPERTYRECOVERY
RUPTURE/DEFORMATION
( SEE “TEMPERATURE” )
Space Environment Effects : Atomic Oxygen
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Silver interconnector flown on Eureca. The silver is oxidised. Silver loss: 1 micron per 1021
atoms
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HIGHVELOCITYPARTICLE IMPACT CRATERING
THROUGHHOLE
CHANGE INTHERMOOPTICAL
PROPERTIES
CONDUCTIVEPATH
LOSS OFMATERIAL
INTEGRITY/CRACK
INITIATION
EXPOSURE OFUNDERLAYER
NUMEROUS PROBLEMSPARTICULARLY
EMBRITTLEMENT/LEAK
ELECTRICALPROBLEMS
DEBRISCONTAMINATION
CLOUD
( SEE “ATOX”)
( SEE“TEMPERATURE”)
Space Environment Effects : Micrometeoroids & Debris
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Cumulative number of impacts in ISS Orbit
10-12
10-10
10-8
10-6
10-4
0.01
1
100
10000
0.0001 0.001 0.01 0.1 1 10
N debrisN meteoroidsN total
Number m-2 year-1
Diameter (cm)
h = 400 km, inclination = 51.6o,year 2000
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Cumulative number of impacts in Polar Orbit
10-12
10-10
10-8
10-6
10-4
0.01
1
100
10000
0.0001 0.001 0.01 0.1 1 10
N debris
N meteoroids
N total
Number m-2 year-1
Diameter (cm)
h = 800 km, inclination i = 98o
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Cumulative number of impacts in GEO
10-10
10-8
10-6
0.0001
0.01
1
100
104
0.0001 0.001 0.01 0.1 1 10
N debrisN meteoroidsN total
Diameter(cm)
Number m-2 year-1
h = 35786 km, inclination i= 0.5o
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HIGHVELOCITYPARTICLE IMPACT CRATERING
THROUGHHOLE
CHANGE INTHERMOOPTICAL
PROPERTIES
CONDUCTIVEPATH
LOSS OFMATERIAL
INTEGRITY/CRACK
INITIATION
EXPOSURE OFUNDERLAYER
NUMEROUS PROBLEMSPARTICULARLY
EMBRITTLEMENT/LEAK
ELECTRICALPROBLEMS
DEBRISCONTAMINATION
CLOUD
( SEE “ATOX”)
( SEE“TEMPERATURE”)
Space Environment Effects : Micrometeoroids & Debris
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Materials and Processes DivisionESA/ESTEC/TEC-QM
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Materials and Processes DivisionESA/ESTEC/TEC-QM
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Space Environment Effects : Re-entry
RUPTURE
LOSSMECHANICALRESISTANCE
ULTRA-HIGHTEMPERATURE
RE-ENTRYDYNAMICPRESSURE
PLASMA CHEMICAL REACTIONS
EROSION/CORROSION
SURFACE TEXTURECHANGES
LOSS OF MATERIALINTEGRITY
MODIFICATION OFHEAT EXCHANGES
NUMEROUS PROBLEMSPARTICULARLY
EMBRITTLEMENT
THERMALPROBLEMS
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Inflatable Re-entry Vehicle
Ablative shield
1st inflatable deceleration unit
2nd inflatable deceleration unit
IRDT
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Re-entry Apollo 8
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NUMEROUS PROBLEMS PARTICULARLY
INSULATION/ GASKETING
DEGRADATION OF MATERIAL FUNCTION
OFFGASSING/AGEING/CORROSION
COMBUSTION
BIOLOGICAL GROWTH
SMELL
LIFE SUPPORTING ATMOSPHERE
TOXIC GASES
LOSS OF MATERIAL FUNCTION
TOXINES
AGRESSIONS TO LIFE
CATASTROPHIC FAILURES
DISEASES
DISCOMFORT
Space Environment Effects : Manned Volumes
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Conclusions
• During the whole lifetime of a spacecraft, materials are subjected to a large number of different environments, some of which can be very harsh and harmful to the integrity or functionality.
• Earth and space environment experienced by a spacecraft must both be considered during the design process.
• Material selection has to be biased towards the specific needs of space programmes. The environmental factors associated with space have a direct influence on material selection. The application dictates the use of a particular material type.
• Interactions between a material and the different environments to which it is exposed are quite often synergistic and not simply additive; i.e. the sum of both interactions is larger than each of the effects separately.
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•Materials require evaluation to ensure adequate performance under a variety of combined conditions.
•Tests must be optimised –differentiate between primary and secondary parameters/degradation mechanisms.
•Simulation of these combined environments–Technical limitations–Cost effectiveness/ affordability
Conclusions (cont.)