scholarly journals A comparison of atomic oxygen erosion yields of carbon and selected polymers exposed in ground based facilities and in low Earth orbit

1994 ◽  
Author(s):  
S. Rutledge ◽  
B. Banks ◽  
M. Cales
Keyword(s):  
Atomic Oxygen ◽  
Low Earth Orbit ◽  
Earth Orbit ◽  
Atomic Oxygen Erosion

Effects of atomic oxygen on epoxy-based shape memory polymer in low earth orbit

2017 ◽  
Vol 29 (6) ◽  
pp. 1081-1087 ◽  
Author(s):  
Qiao Tan ◽  
Fengfeng Li ◽  
Liwu Liu ◽  
Hetao Chu ◽  
Yanju Liu ◽  
...  
Keyword(s):  
Shape Memory ◽  
Atomic Oxygen ◽  
Shape Memory Polymer ◽  
Mechanical Tests ◽  
Low Earth Orbit ◽  
Earth Orbit ◽  
Oxygen Exposure ◽  
Static Mechanical ◽  
Atomic Oxygen Erosion ◽  
Atomic Oxygen Exposure

Atomic oxygen is a dominant component of the low earth orbit and can erode most spacecraft polymeric material. In this article, the atomic oxygen erosion resistance tests of an epoxy-based shape memory polymer are carried out in a ground-based atomic oxygen simulator with a vacuum space chamber. The samples, before and after the atomic oxygen exposure, are compared in appearance, surface morphology, mass, main component, dynamical and static mechanical properties, and shape memory properties. The atomic oxygen exposure causes oxidization reaction of the material, which leads to surface roughen and mass loss, while the shape memory polymer main components remain same. The results of dynamical and static mechanical tests indicate that the atomic oxygen exposure has little effect on the storage modulus and glassy transition temperature (Tg), whereas the elongation, elastic modulus, tensile strength, and yield strength decrease since the atomic oxygen exposure gives rise to tiny cracks. The shape memory property has rarely changed since the atomic oxygen erosion is mainly located near the surface of the sample.

scholarly journals The Effect of Low Earth Orbit Atomic Oxygen Exposure on Phenylphosphine Oxide-Containing Polymers

2000 ◽  
Vol 12 (1) ◽  
pp. 43-52 ◽  
Author(s):  
John W Connell
Keyword(s):  
Thin Film ◽  
Atomic Oxygen ◽  
Low Earth Orbit ◽  
Space Environment ◽  
Earth Orbit ◽  
Cooperative Effort ◽  
Flight Experiment ◽  
Oxygen Exposure ◽  
Atomic Oxygen Exposure ◽  
Phenylphosphine Oxide

Thin films of phenylphosphine oxide-containing polymers were exposed to low Earth orbit aboard a space shuttle flight (STS-85) as part of flight experiment designated Evaluation of Space Environment and Effects on Materials (ESEM). This flight experiment was a cooperative effort between the NASA Langley Research Center (LaRC) and the National Space Development Agency of Japan (NASDA). The thin-film samples described herein were part of an atomic oxygen exposure (AOE) experiment and were exposed to primarily atomic oxygen (∼1×1019 atoms cm−2). The thin-film samples consisted of three phosphine oxide-containing polymers (arylene ether, benzimidazole and imide). Based on post-flight analyses using atomic force microscopy, x-ray photo-electron spectroscopy and weight loss data, it was found that the exposure of these materials to atomic oxygen (AO) produces a phosphorus oxide layer on the surface of the samples. Earlier work has shown that this layer provides a barrier towards further attack by AO. Consequently, these materials do not exhibit linear erosion rates which is in contrast with most organic polymers. Qualitatively, the results obtained from these analyses compare favourably with those obtained from samples exposed to AO and/or an oxygen plasma in ground-based exposure experiments. The results of the low Earth orbit AO exposure on these materials will be compared with those of ground-based exposure to AO.

Concentration of atomic oxygen in low earth orbit and in the laboratory for use in high quality oxide thin film growth

1998 ◽  
Author(s):  
J. A. Schultz ◽  
K. Eipers-Smith ◽  
K. Waters ◽  
S. Schultz ◽  
M. Sterling ◽  
...  
Keyword(s):  
Thin Film ◽  
Atomic Oxygen ◽  
Film Growth ◽  
Low Earth Orbit ◽  
Thin Film Growth ◽  
Oxide Thin Film ◽  
Earth Orbit ◽  
High Quality

Atomic Oxygen Plasma Effects on Cvd Deposited Diamond-Like Carbon Films

1991 ◽  
Vol 236 ◽  
Author(s):  
Jeffrey S. Hale ◽  
R.A. Synowicki ◽  
S. Nafis ◽  
John A. Woollam
Keyword(s):  
Atomic Oxygen ◽  
Moisture Absorption ◽  
Crystalline Silicon ◽  
Carbon Films ◽  
Fused Silica ◽  
Low Earth Orbit ◽  
Index Of Refraction ◽  
Earth Orbit ◽  
Diamond Like Carbon ◽  
Space Flights

AbstractCVD deposited diamond-like carbon (DLC) films have been studied for possible use as a secondary standard for Low Earth Orbit materials degradation. Samples of various thicknesses have been exposed to a simulated Low Earth Orbit atomic oxygen (AO) environment using a plasma asher. Mass loss measurements indicate that DLC degrades at a rate of 0.7 mg/hr which is two to three times the rate of currently used Kapton samples which degrade at a rate of.3 mg/hr. Thickness measurements show that DLC thins at a rate of 77 Angstroms/min. Since DLC is not as susceptible to environmental factors such as moisture absorption, it could potentially provide more accurate measurements of AO fluence on short space flights. Adhesion of DLC films to both fused silica and crystalline silicon substrates has been studied under thermal cycling conditions. Film adhesion to fused silica can be enhanced by sputtering a thin layer of silicon dioxide onto the substrate prior to deposition. In addition to the above, the index of refraction and extinction coefficient of various thicknesses of DLC films has been characterized by Variable Angle Spectroscopic Ellipsometry.

A Magnetically Filtered Atomic Oxygen Plasma Source for Low-Earth-Orbit Simulation

2021 ◽  
pp. 1-10
Author(s):  
Carlos A. Maldonado ◽  
Andrew D. Ketsdever ◽  
John D. Williams
Keyword(s):  
Atomic Oxygen ◽  
Oxygen Plasma ◽  
Plasma Source ◽  
Low Earth Orbit ◽  
Earth Orbit
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