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Book Determination of Ground Laboratory to In Space Effective Atomic Oxygen Fluence for DC 93 500 Silicone

Download or read book Determination of Ground Laboratory to In Space Effective Atomic Oxygen Fluence for DC 93 500 Silicone written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-24 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this research was to calibrate the ground-to-space effective atomic oxygen fluence for DC 93-500 silicone in a thermal energy electron cyclotron resonance (ECR) oxygen plasma facility. Silicones, commonly used spacecraft materials, do not chemically erode with atomic oxygen attack like other organic materials but form an oxidized hardened silicate surface layer. Therefore, the effective atomic oxygen fluence in a ground test facility should not be determined based on mass loss measurements, as they are with organic polymers. A technique has been developed at the Glenn Research Center to determine the equivalent amount of atomic oxygen exposure in an ECR ground test facility to produce the same degree of atomic oxygen damage as in space. The approach used was to compare changes in the surface hardness of ground test (ECR) exposed DC 93-500 silicone with DC 93-500 exposed to low Earth orbit (LEO) atomic oxygen as part of a shuttle flight experiment. The ground to in-space effective atomic oxygen fluence correlation was determined based on the fluence in the ECR source that produced the same hardness for the fluence in-space. Nanomechanical hardness versus contact depth measurements were obtained for five ECR exposed DC 93-500 samples (ECR exposed for 18 to 40 hrs, corresponding to Kapton effective fluences of 4.2 x 10(exp 20) to 9.4 x 10(exp 20) atoms/sq cm, respectively) and for space exposed DC 93-500 from the Evaluation of Oxygen Interactions with Materials III (EOIM III) shuttle flight experiment, exposed to LEO atomic oxygen for 2.3 x 10(exp 20) atoms/sq cm. Pristine controls were also evaluated. A ground-to-space correlation value was determined based on correlation values for four contact depths (150, 200, 250, and 300 nm), which represent the near surface depth data. The results indicate that the Kapton effective atomic oxygen fluence in the ECR facility needs to be 2.64 times higher than in LEO to replicate equivalent exposure damage in the g

Book Protection of Materials and Structures from the Space Environment

Download or read book Protection of Materials and Structures from the Space Environment written by Jacob I. Kleiman and published by Springer Science & Business Media. This book was released on 2006-07-13 with total page 456 pages. Available in PDF, EPUB and Kindle. Book excerpt: The effects of various space environment factors like atomic oxygen, vacuum ultraviolet radiation, charging, micrometeoroids, meteoroid showers, etc. on materials and structures in various orbits are discussed. In addition the ways to prevent these effects or reduce them through protection by coatings or modification of affected surfaces are considered in the book. The discussions on development of predictive models of material erosion that will allow the materials engineers and designers of future spacecraft to evaluate materials' behaviour is continued from the past meetings.

Book Research Technology 2004

    Research Technology 2004

    Book Details:
  • Author :
  • Publisher : DIANE Publishing
  • Release :
  • ISBN : 1428918183
  • Pages : 226 pages

Download or read book Research Technology 2004 written by and published by DIANE Publishing. This book was released on with total page 226 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Protection of Materials and Structures from the Low Earth Orbit Space Environment

Download or read book Protection of Materials and Structures from the Low Earth Orbit Space Environment written by J. Kleiman and published by Springer Science & Business Media. This book was released on 2013-11-11 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt: This publication presents the proceedings of ICPMSE-3, the third international conference on Protection of Materials and Structures from the Low Earth Orbit Space Environment, held in Toronto April 25-26, 1996. The conference was hosted and organized by Integrity Testing Laboratory Inc, (ITL), and held at the University of Toronto's Institute for Aerospace Studies (UTIAS), where ITL is located. Twenty industrial companies, seven wliversities and eight government agencies from Canada, USA, United Kingdom, France, Israel, Russia, Ukraine and the Netherlands were represented by over 55 participants indicating increasing international co-operation in this critical arena of protection of materials in space. Twenty-five speakers, world experts in their fields, delivered talks on a wide variety of topics on various aspects of material protection in space, Representatives from the Canadian, American, European and Israeli space agencies as well as from leading space research laboratories of major aerospace industries gathered at UTIAS to discuss the latest developments in the field of material and structure protection from the harsh space environment, These proceedings are organized into four sections: a) AONOV and Radiation Effects on Materials and Structures in the Leo Space Environment; b) Interaction of Matter with the LEO Environment; c) Large Scale Coating Process Developments for Protection in LEO; d) Synthesis and Modification of Materials and Surfaces for Protection in LEO, This is the third in our on-going series of bi-annual international space materials conferences wllich began in 1992 in Toronto. Jacob Kleiman, Integrity Testing Laboratory Inc.

Book 32nd Aerospace Sciences Meeting Exhibit 94 0360 94 0389

Download or read book 32nd Aerospace Sciences Meeting Exhibit 94 0360 94 0389 written by and published by . This book was released on 1994 with total page 438 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Low Earth Orbit Durability Evaluation of Protected Silicone for Advanced Refractive Photovoltaic Concentrator Arrays

Download or read book Low Earth Orbit Durability Evaluation of Protected Silicone for Advanced Refractive Photovoltaic Concentrator Arrays written by Kim K. De Groh and published by . This book was released on 1994 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: The need for efficient, cost effective sources of electrical power in space has led to the development of photovoltaic power systems which make use of novel refractive solar concentrators. These concentrators have been conceived in both point-focus and linear-focus designs. Current concentrator lenses are fabricated from flexible silicones with Fresnel facets along their inside surface. To insure the efficient operation of these power systems, the concentrator lenses must be durable and the silicone material must remain specularly transmitting over a reasonable lifetime in low Earth orbit (LEO) and other space environments. Because of the vulnerability of silicones to atomic oxygen and ultraviolet radiation in LEO these lenses have been coated with a multi-layer metal oxide protective coating. The objective of this research was to evaluate the LEO durability of the multilayer coated silicone for advanced refractive photovoltaic concentrator arrays with respect to optical properties and microstructure. Flat metal oxide coated silicone samples were exposed to ground-laboratory and in-space atomic oxyqen for durability evaluation.

Book Flight And Ground Test Correlation Study of Bmdo Sds Materials

Download or read book Flight And Ground Test Correlation Study of Bmdo Sds Materials written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-24 with total page 272 pages. Available in PDF, EPUB and Kindle. Book excerpt: The NASA Evaluation of Oxygen Interactions with Materials-3 (EOIM-3) experiment served as a test bed for a variety of materials that are candidates for Ballistic Missile Defense Organization (BMDO) space assets. The materials evaluated on this flight experiment were provided by BMDO contractors and technology laboratories. A parallel ground exposure evaluation was conducted using the FAST atomic-oxygen simulation facility at Physical Sciences, Inc. The EOIM-3 materials were exposed to an atomic oxygen fluence of approximately 2.3 x 10(exp 2) atoms/sq. cm. The ground-exposed materials' fluence of 2.0 - 2.5 x 10(exp 2) atoms/sq. cm permits direct comparison of ground-exposed materials' performance with that of the flight-exposed specimens. The results from the flight test conducted aboard STS-46 and the correlative ground exposure are presented in this publication. Chung, Shirley Y. and Brinza, David E. and Minton, Timothy K. and Stiegman, Albert E. and Kenny, James T. and Liang, Ranty H. Jet Propulsion Laboratory NASA-CR-196451, JPL-PUBL-93-31, NAS 1.26:196451 NAS7-918...

Book Use of Atomic Oxygen for the Determination of Document Alteration

Download or read book Use of Atomic Oxygen for the Determination of Document Alteration written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-12 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: Atomic oxygen, which normally is found only the near Earth space environment, causes oxidation and erosion of polymers on spacecraft. The development of technology to prevent this degradation has required NASA to develop ground laboratory facilities that generate atomic oxygen. Atomic oxygen has also been found to be able to oxidize most types of ink from a variety of types of pens. The use of atomic oxygen to identify alteration of documents has been investigated and is reported. Results of testing indicates that for many types of ink, pen, and paper, identification of document alteration of pen and ink numbers and evidence of alteration can be made visible by exposing the questionable writing to atomic oxygen. Atomic oxygen provides discrimination because different inks may oxidize at different rates, the amount of time between delayed alteration may add to ink thickness at crossings, and the end of pen strokes tend to have much thicker ink deposits than the rest of the character. Examples and techniques of using atomic oxygen to identify document alteration indicate that the technology can, in many but not all cases, provide discrimination between original and altered documents.Banks, Bruce A. and Klubnik, Larisa M.Glenn Research CenterOXYGEN ATOMS; DOCUMENTS; INKS; PAPER (MATERIAL); TECHNOLOGY UTILIZATION; AEROSPACE TECHNOLOGY TRANSFER; OXIDATION

Book Atomic Oxygen Protection of Materials in Low Earth Orbit

Download or read book Atomic Oxygen Protection of Materials in Low Earth Orbit written by and published by . This book was released on 2002 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book A Sensitive Technique Using Atomic Force Microscopy to Measure the Low Earth Orbit Atomic Oxygen Erosion of Polymers

Download or read book A Sensitive Technique Using Atomic Force Microscopy to Measure the Low Earth Orbit Atomic Oxygen Erosion of Polymers written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-05-29 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt: Polymers such as polyimide Kapton and Teflon FEP (fluorinated ethylene propylene) are commonly used spacecraft materials due to their desirable properties such as flexibility, low density, and in the case of FEP low solar absorptance and high thermal emittance. Polymers on the exterior of spacecraft in the low Earth orbit (LEO) environment are exposed to energetic atomic oxygen. Atomic oxygen erosion of polymers occurs in LEO and is a threat to spacecraft durability. It is therefore important to understand the atomic oxygen erosion yield (E, the volume loss per incident oxygen atom) of polymers being considered in spacecraft design. Because long-term space exposure data is rare and very costly, short-term exposures such as on the shuttle are often relied upon for atomic oxygen erosion determination. The most common technique for determining E is through mass loss measurements. For limited duration exposure experiments, such as shuttle experiments, the atomic oxygen fluence is often so small that mass loss measurements can not produce acceptable uncertainties. Therefore, a recession measurement technique has been developed using selective protection of polymer samples, combined with postflight atomic force microscopy (AFM) analysis, to obtain accurate erosion yields of polymers exposed to low atomic oxygen fluences. This paper discusses the procedures used for this recession depth technique along with relevant characterization issues. In particular, a polymer is salt-sprayed prior to flight, then the salt is washed off postflight and AFM is used to determine the erosion depth from the protected plateau. A small sample was salt-sprayed for AFM erosion depth analysis and flown as part of the Limited Duration Candidate Exposure (LDCE-4,-5) shuttle flight experiment on STS-51. This sample was used to study issues such as use of contact versus non-contact mode imaging for determining recession depth measurements. Error analyses were conducted and the percent probable erro

Book Atomic Oxygen and Space Environment Effects on Aerospace Materials Flown with Eoim 3 Experiment

Download or read book Atomic Oxygen and Space Environment Effects on Aerospace Materials Flown with Eoim 3 Experiment written by National Aeronautics and Space Adm Nasa and published by Independently Published. This book was released on 2018-11-02 with total page 70 pages. Available in PDF, EPUB and Kindle. Book excerpt: Polymer materials samples mounted on a passive carrier tray were flown aboard the STS-46 Atlantis shuttle as complement to the EOIM-3 (Evaluation of Oxygen Interaction with Materials) experiment to evaluate the effects of atomic oxygen on the materials and to measure the gaseous shuttle bay environment. The morphological changes of the samples produced by the atomic oxygen fluence of 2.07 x 10(exp 20) atoms/cm(exp 2) are being reported. The changes have been verified using Electron Spectroscopy for Chemical Analysis (ESCA), gravimetric measurement, microscopic observations and thermo-optical measurements. The samples, including Kapton, Delrin, epoxies, Beta Cloth, Chemglaze Z306, silver Teflon, silicone coatings, 3M tape and Uralane and Ultem, PEEK, Victrex (PES), Polyethersulfone and Polymethylpentene thermoplastic, have been characterized by their oxygen reaction efficiency on the basis of their erosion losses and the oxygen fluence. Those efficiencies have been compared to results from other experiments, when available. The efficiencies of the samples are all in the range of E-24 g/atom. The results indicate that the reaction efficiencies of the reported materials can be grouped in about three ranges of values. The least affected materials which have efficiencies varying from 1 to 10(exp 25) g/atom, include silicones, epoxies, Uralane and Teflon. A second group with efficiency from 10 to 45(exp 25) g/atom includes additional silicone coatings, the Chemglaze Z306 paint and Kapton. The third range from 50 to 75(exp 25) includes organic compound such as Pentene, Peek, Ultem, Sulfone and a 3M tape. A Delrin sample had the highest reaction efficiency of 179(exp 25) g/atom. Two samples, the aluminum Beta cloth X389-7 and the epoxy fiberglass G-11 nonflame retardant, showed a slight mass increase. Scialdone, John J. and Clatterbuck, Carroll H. and Ayres-Treusdell, Mary and Park, Gloria and Kolos, Diane Goddard Space Flight Center...

Book Atomic Oxygen Exposure of LDEF Experiment Trays

Download or read book Atomic Oxygen Exposure of LDEF Experiment Trays written by Roger J. Bourassa and published by . This book was released on 1992 with total page 368 pages. Available in PDF, EPUB and Kindle. Book excerpt: