scholarly journals Oxidation and Protection of Fiberglass-Epoxy Composite Masts for Photovoltaic Arrays in the Low Earth Orbital Environment

1988 ◽  
Vol 125 ◽  
Author(s):  
Sharon K. Rutledge ◽  
Phillip E. Paulsen ◽  
Joyce A. Brady ◽  
Michael L. Ciancone
Keyword(s):  
Atomic Oxygen ◽  
Epoxy Composite ◽  
Glass Fibers ◽  
Space Station ◽  
Epoxy Composites ◽  
Solar Array ◽  
Structural Members ◽  
Oxygen Environment ◽  
Photovoltaic Arrays ◽  
Accelerate Degradation

ABSTRACTFiberglass-epoxy composites have been considered for use as structural members for the mast of the Space Station solar array panel. The low Earth orbital environment in which Space Station is to operate is composed mainly of atomic oxygen, which has been shown to cause erosion of many organic materials and some metals. Ground based testing in a plasma asher was performed in order to determine the extent of degradation of fiberglass-epoxy composites when exposed to a simulated atomic oxygen environment. During exposure, the epoxy at the surface of the composite was oxidized, exposing individual glass fibers which could easily be removed. Several methods of protecting the composite were evaluated in an atomic oxygen environment and with thermal cycling and flexing: The protection techniques evaluated to date include an aluminum braid covering, an indium-tin eutectic and a silicone based paint. The open aluminum braid offered little protection while the CV-1144 coating offered some initial protection against atomic oxygen. The In-Sn eutectic coating provided initial protection against atomic oxygen, but appears to develop cracks which accelerate degradation by atomic oxygen when flexed. Coatings such as the In-Sn eutectic may provide adequate protection by containing the glass fibers even though mass loss still occurs.

Shuttle and MIR Special Environmental Effects and Hardware Cleanliness

2000 ◽  
Vol 12 (1) ◽  
pp. 65-82 ◽  
Author(s):  
Gale A Harvey ◽  
Donald H Humes ◽  
William H Kinard
Keyword(s):  
Environmental Effects ◽  
Atomic Oxygen ◽  
Risk Mitigation ◽  
Space Station ◽  
The United States ◽  
Water Soluble ◽  
Space Environment ◽  
Electrical Performance ◽  
Solar Array ◽  
Flight Hardware

The Evaluation of Space Environment and Effects on Materials (ESEM) experiments were developed, flown in-space on the STS-85 mission (August 1997), returned to Earth and analysed as one element of a collaboration between the National Space Development Agency (NASDA) of Japan and the National Aeronautics and Space Agency (NASA) of the United States. The primary objectives of the ESEM experiments were to investigate atomic oxygen effects on materials, cosmic dust and man-made debris, and Shuttle-induced contamination. In particular, the change in scattering of light from the 1/4 mil aluminized Kapton film due to atomic oxygen erosion and Shuttle-induced molecular contamination are discussed. The MIR environmental effects payload (MEEP) was attached to the docking module of the MIR space station for 18 months during calendar years 1996 and 1997 (March 1996, STS 76 to October 1997, STS 86). A solar panel array with more than 10 years space exposure was removed from the MIR core module in November 1997 and returned to Earth in January 1998, STS 89. MEEP and the returned solar array are part of the International Space Station (ISS) Risk Mitigation Program. This space flight hardware has been inspected and studied by teams of space environmental effects (SEE) investigators for micrometeoroid and space debris effects, space exposure effects on materials and electrical performance. This paper reports changes in cleanliness of parts of MEEP and the solar array due to the space exposures. Special attention is given to the extensive water soluble residues deposited on some of the flight hardware surfaces. Directionality of deposition and chemistry of these residues are discussed.

Evaluation of Lamina Properties and Fractographic Studies on Glass/Epoxy, Carbon/Epoxy and Kevlar/Epoxy Composites

2015 ◽  
Vol 813-814 ◽  
pp. 46-50 ◽  
Author(s):  
Julias A. Arockia ◽  
Kumar N. Ram ◽  
Murali Vela
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Tensile Test ◽  
Epoxy Composite ◽  
Epoxy Composites ◽  
Strain Gauges ◽  
Transverse Strain ◽  
Molding Machine ◽  
Mechanism Of Failure ◽  
Scanning Electron

In this study the lamina properties of glass/epoxy, carbon/epoxy and kevlar/epoxy composite along their principal coordinate axes were evaluated by performing tensile test. The laminates were prepared by hand lay-up technique and compressed using a compression molding machine at 70 oc and 80 bar pressure. The test was conducted as per ASTM standard D3039 by affixing strain gauges in the specimen to obtain the longitudinal and transverse strain. The mechanism of failure was also studied by performing fractographic analysis using scanning electron microscope which shows peeled off fiber surfaces in the case of kevlar/epoxy laminate.

scholarly journals Experimental and Numerical Study on the Effect of Creep Behavior on Epoxy Composites Reinforced with Yttrium Oxide Powder

2020 ◽  
Vol 25 (4) ◽  
pp. 203-213
Author(s):  
B.H. Abed ◽  
K.J. Jadee ◽  
A.A. Battawi
Keyword(s):  
Mechanical Properties ◽  
Composite Material ◽  
Elasticity Modulus ◽  
Epoxy Composite ◽  
Numerical Study ◽  
Creep Behaviour ◽  
Weight Ratio ◽  
Volume Ratio ◽  
Epoxy Composites ◽  
Creep Characteristics

AbstractThe creep test is one of the important approaches to determining some mechanical properties of composite materials. This study was carried out to investigate the creep behaviour of an epoxy composite material that was reinforced with Y2O3 powder at weight ratios of 2%, 7%, 12%, 17% and 22%. Each volume ratio was subjected to five loads over the range of 1N to5N at a constant temperature of 16 ± 2°C. In this work, creep behaviour, stress and elasticity modulus were studied through experimental and numerical analyses. Results showed that increasing the weight ratio of Y2O3 powder enhanced creep characteristics.

scholarly journals Effect of Filler Nature on Chemical Resistance and Microhardness of Epoxy Composite Films

2015 ◽  
Vol 16 (3) ◽  
pp. 528-533
Author(s):  
G. Martinyuk ◽  
O. Aksimentyeva ◽  
N. Skoreiko ◽  
V. Zakordonskyi
Keyword(s):  
Mechanical Properties ◽  
Chemical Resistance ◽  
Filler Content ◽  
Epoxy Composite ◽  
Composite Films ◽  
Physical And Mechanical Properties ◽  
Epoxy Composites ◽  
Mineral Filler ◽  
Operating Characteristics ◽  
Mineral Fillers

We investigated the processes of water absorption, chemical stability and microhardness of films of epoxy composites that contained as the polymer matrix the epoxy resin UP-655 and mineral fillers: graphite, mica, aluminum oxide at their content (0 - 30 % mass). It found that introduction of mineral fillers significantly affects on all complex of operating characteristics of the films. Increase of filler content, especially mica, to 20 %, resulting in slower process and reducing the quantity of absorbed moisture by films. In the study of physical and mechanical properties of filled epoxy composites was established that the introduction of mineral filler significantly affects their microhardness, and the nature of the exposure is determined by the type and filler content.

Planning solar array operations on the international space station

2011 ◽  
Vol 2 (4) ◽  
pp. 1-24 ◽  
Author(s):  
Sudhakar Y. Reddy ◽  
Jeremy D. Frank ◽  
Michael J. Iatauro ◽  
Matthew E. Boyce ◽  
Elif Kürklü ◽  
...  
Keyword(s):  
International Space Station ◽  
Space Station ◽  
Solar Array ◽  
International Space

Developing methods for taking into account the radiation coming from Earth in simulations of incoming electric power on the Russian Segment of the International Space Station in experiment Albedo

2021 ◽  
pp. 125-140
Author(s):  
Dmitriy N. RULEV
Keyword(s):  
Electric Power ◽  
International Space Station ◽  
Power Supply ◽  
Power Supply System ◽  
Space Station ◽  
Power Input ◽  
Solar Array ◽  
International Space ◽  
Solar Arrays ◽  
Array Performance

The paper describes the implementation of space experiment Albedo, which provided a framework for developing methods of taking into account the radiation emitted by the system «atmosphere–underlying terrain» in simulations of the operation of the power supply system of the Russian Segment of the International Space Station. As a result of the implementation of the space experiment a procedure was developed for determining and using characteristics of radiation coming from Earth in the simulation of a space station power supply system, including procedures and special software for determining solar array performance and simulating power input coming from solar arrays taking into account Earth albedo, as well as recommendations are given for the control modes of power supply systems of orbital spacecraft. As a result of testing computational schemes for evaluating the solar array performance and simulating electric power output that takes into account the Earth albedo, substantiated values were obtained for the proposed reference parameter for evaluating the performance of solar arrays of the Service Module of the International Space Station. Key words: Russian Segment of the International Space Station, solar arrays, electric power input, solar array performance estimate, radiation coming from Earth, albedo.

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