MATERIALS AND PROCESSES

Pippin*, G., Development of a Spacecraft Materials Selector Expert System, NASA/CR-2002-211785, George C. Marshall Space Flight Center , Marshall Space Flight Center, AL 35812, National Aeronautics and Space Administration, Washington, DC 20546-0001, Prepared for NASA's Space Environments and Effects (SEE) Program * The Boeing Company; Technical Mon, June, 2002, pp. 40

Keywords:  on-orbit material performance, spacecraft materials selector

Abstract:  This report contains a description of the knowledge base tool and examples of its use. A downloadable version of the Spacecraft Materials Selector (SMS) knowledge base is available through the NASA Space Environments and Effects Program. The "Spacecraft Materials Selector" knowledge base is part of an electronic expert system. The expert system consists of an inference engine that contains the "decision-making" code and the knowledge base that contains the selected body of information. The inference engine is a software package previously developed at Boeing, called the Boeing Expert System Tool (BEST) kit.

R.J.Mell* and G.E. Wertz, Testing and Optimization of Electrically Conductive Spacecraft Coatings, NASA/CR-2001-211411, George C. Marshall Space Flight Center Marshall Space Flight Center, AL 35812, AZ Technology, Inc. 7047 Old Madison Pike, Suite 300 Huntsville, AL 35806, Prepared for NASA's Space Environment and Effects (SEE) Program, *AZ Technology, Inc.; Technical Monitor: D.L. Edwards, December 2001, pp. 60.

Keywords: surface charging, coatings, thermal control

Abstract: This is the final report discussing the work done for the Space environments and Effects (SEE) Program. It discusses test chamber design, coating research, and test results on electrically thermal control coatings. These thermal control coatings are being developed to have several orders of magnitude higher electrical conductivity than most available thermal control coatings. Most current coatings tend to have a range in surface resistivity from 1,001 to 1,013 ohms/sq.

Historically, spacecraft have had thermal control surfaces composed of dielectric materials of either polymers (paints and metalized films) or glasses (ceramic paints and optical solar reflectors). Very seldom has the thermal control surface of a spacecraft been a metal where the surface would be intrinsically electrically conductive. The poor thermal optical properties of most metals have, in most cases, stopped them from being used as a thermal control surface. Metals low infrared emittance (generally considered poor for thermal control surfaces) and/or solar absorptance, have resulted in the use of various dielectric coatings or films being applied over the substrate materials in order to obtain the required optical properties.

D.R. Wilkes and J.M. Zwiener, Science Data Report for the Optical Properties Monitor (OPM) Experiment, NASA/CR-2001-210881, George C. Marshall Space Flight Center Marshall Space Flight Center, AL 35812, AZ Technology, Inc.  Huntsville, AL 35806, Prepared for Materials Processes and Manufacturing Department, Engineering Directorate Technical Monitor: Ralph Carruth, March 2001, pp. 265.

G. Swenson, Vehicle/Atmosphere Interaction Glows:  Far Ultraviolet, Visible, and Infrared, NASA/CR-1999-209254, Prepared for NASA's Space Environments and Effects (SEE) Program NASA Marshall Space Flight Center, Alabama 35812, October 1999, pp 36

Keywords:  spacecraft glow, FUV, UV, visible, infrared

Abstract:  Spacecraft glow information has been gathered from a number of spacecraft including Atmospheric and Dynamic satellites, and Space Shuttles (numerous flights) with dedicated pallet flow observations on STS-39 (DOD) and STS-62 (NASA).  In addition, a larger number of laboratory experiments with low energy oxygen beam studies have made important contributions to glow understanding.  The following report provides information on three engineering models developed for spacecraft glow including the far ultraviolet to ultraviolet (1400-4000 A), and infrared (0.9-40 U) spectral regions.  The models include effects resulting from atmospheric density/altitude, spacecraft temperature, spacecraft material, and ram angle.  Glow brightness would be predicted as a function of distance from surfaces for all wavelengths.

D. Dooling and M.M. Finckenor , Material Selection Guidelines to Limit Atomic Oxygen Effects on Spacecraft Surfaces, NASA/TP -1999-209260, Prepared for NASA's Space Environments and Effects (SEE) Program *D2 Associates,  Huntsville, AL 35816 , June 1999 , pp. 44 .

Keywords: materials, space materials

Abstract: Material Selection Guidelines to Limit Atomic Oxygen Effects on Spacecraft Surfaces provides guidelines in selecting materials for satellites and space platforms, designed to operate within the Low-Earth orbit environment, which limit the effects of atomic oxygen interactions with spacecraft surfaces. This document should be treated as an introduction rather than a comprehensive guide since analytical and flight technologies continue to evolve, flight experiments are conducted as primary or piggyback opportunities arise, and our understanding of materials interactions and protection methods grows. The reader is urged to consult recent literature and current web sites containing information about research and flight results.

M.M. Finckenor and D. Dooling , Multilayer Insulation Material Guidelines , NASA/TP -1999-209263, Prepared for NASA's Space Environments and Effects (SEE) Program *D2 Associates, Huntsville, AL 35816 , April 1999 , pp. 44 .

Keywords: materials, space materials

Abstract: Multilayer Insulation Material Guidelines provides data on multilayer insulation materials used by previous spacecraft such as Spacelab and the Long-Duration Exposure Facility and outlines other concerns. The data presented in the document are presented for information only. They can be used as guidelines for multilayer insulation design for future spacecraft provided the thermal requirements of each new design and the environmental effects on these materials are taken into account.

M. S. Deshpande and Y. Harada, Development of Tailorable Electrically Conductive Thermal Control Material Systems, NASA/CR-1998-208474, NASA Marshall Space Flight Center, AL 35812, June 1998, pp. 311.

Keywords: Materials, Electrically Conductive Materials, Spacecraft Charging

Abstract: The optical characteristics of surfaces on spacecraft are fundamental parameters in controlling its temperature. Passive thermal control coatings with designed solar absorptance and infrared emittance properties have been developed and been in use for some time. In this total space environment, the coating must be stable and maintain its desired optical properties for the course of the mission lifetime. The mission lifetimes are increasing and in our quest to save weight, newer substrates are being integrated which limit electrical grounding schemes. All of this has already added to the existing concerns about spacecraft charging and related spacecraft failures or operational failures. The concern is even greater for thermal control surfaces that are very large. One way of alleviating such concerns is to design new thermal control material systems (TCMS) that can help to mitigate charging via providing charge leakage paths. The object of this program was to develop two types of passive electrically conductive TCMS.

Edward M. Silverman, Space Environmental Effects on Spacecraft: LEO Materials Selection Guide, Contract NAS1-19291 (NASA CR-4661, Part 1 & Part 2) April 1993 through March 1995, TRW Space & Electronics Group, Redondo Beach, California

Abstract: This document provides performance properties on major spacecraft materials and subsystems that have been exposed to the low-Earth (LEO) space environment.  Spacecraft materials include metals, polymers, composites, white and black paints, thermal-control blankets, adhesives, and lubricants.  Spacecraft subsystems include optical components, solar cells, and electronics.  Information has been compiled from LEO short-term spaceflight experiments (e.g., Space Shuttle) and from retrieved satellites of longer mission durations (e.g., Long Duration Exposure Facility).  Major space environment effects include atomix oxygen, ultraviolet radiation, micrometeoroids and debris, contamination, and particle radiation.  The main objective of this document is to provide a decision tool to designers for designing spacecraft and structures.  This document identifies the space environments that will affect the performance of materials and components, e.g., thermal-optical property changes of paints due to UV exposures, AO-induced surface erosion of composites, dimensional changes due to thermal cycling, vacuum-induced moisture outgassing, and surface optical changes due to AO/UV exposures.  Where appropriate, relationships between the space environment and the attendant material/system effects are identified.

D.L. Edwards, Evaluation of Chemical Conversion Material (Protective Coating) Exposed to Space Environmental Conditions, CDDF Final Report (No. 90-07), NASA TM-108416, Materials and Processes Laboratory, NASA Marshall Space Flight Center, AL 35812, July 1993, (N93-32366).

Abstract: This report focuses on the development of an operational Rutherford backscattering spectrometry (RBS) system and shows the application of such a system on a space environmental test. Thin films of aluminum and tantalum were deposited on diamond substrates. These films were anodized and preexposure characterization spectra obtained using RBS and total hemispherical reflectance. The samples were exposed to energetic protons then postexposure characterization spectra was obtained using the same techniques. Conclusions based on the comparison of preexposure and postexposure spectra are presented. RBS comparison spectra show no change in the metal/metal oxide interface, while the comparison reflectance data indicate change. Explanations for this reflectance change are presented in this report.

R.C. Linton, M.M. Finckenor, R.R. Kamenetzky and P. Gray, Effects of Atomic Oxygen and Ultraviolet Radiation on Candidate Elastomeric Materials for Long Duration Missions—Test Series No. 1, NASA TM-108408, Materials and Processes Laboratory, NASA Marshall Space Flight Center, AL 35812, June 1993, (N93-29193).

Abstract: Research has been conducted at the Marshall Space Flight Center on the behavior of elastomeric materials after exposure to simulated space environment. Silicone S383 and Viton V747 samples were exposed to thermal vacuum, ultraviolet (UV) radiation, and atomic oxygen and then evaluated for changes in material properties. Characteri-zation of the elastomeric materials included weight, hardness, optical inspection under normal and black light, spectrofluorescence, solar absorptance and emittance, Fourier transform infrared spectroscopy, and permeability. These results indicate a degree of sensitivity to exposure and provide some evidence of UV and atomic oxygen synergism.

M.D. Danford, The Corrosion Protection of Metals by Ion Vapor Deposited Aluminum, NASA TM-108425 , Materials and Processes Laboratory, NASA Marshall Space Flight Center, AL 35812, October 1993, (N94-15832).

Abstract: A study of the corrosion protection of substrate metals by ion vapor deposited aluminum (IVD Al) coats has been carried out. Corrosion protection by both anodized and unanodized IVD Al coats has been investigated. Base metals included in the study were 2219-T87 Al, 7075-T6 Al, Titanium-6 Al-4 Vanadium (Ti-6Al-4V), 4130 steel, D6AC steel, and 4340 steel. Results reveal that the anodized IVD Al coats provide excellent corrosion protection, but good protection is also achieved by IVD Al coats that have not been anodized.

M.D. Danford, D.W. Walsh* and M.J. Mendrek, The Corrosion Protection of 2219-T87 Aluminum by Organic and Inorganic Zinc-Rich Primers, NASA TP-3534, Materials and Processes Laboratory, Science and Engineering Directorate. NASA Marshall Space Flight Center, AL 35812, *California Polytechnic State University., February 1995, pp. 16.

Keywords: corrosion of coated metals, primer-coated 2219 Al, organic and inorganic zinc-rich primer

Abstract: The behavior of zinc-rich primer-coated 2219-T87 aluminum in a 3.5-percent Na-Cl was investigated using electrochemical techniques. The alternating current (ac) method of electrochemical impedance spectroscopy (EIS), in the frequency range of 0.001 to 40,000 Hz, and the direct current (dc) method of polarization resistance (PR) were used to evaluate the characteristics of an organic, epoxy zinc-rich primer and an inorganic, ethyl silicate zinc-rich primer. A dc electrochemical galvanic corrosion test was also used to determine the corrosion current of each zinc-rich primer anode coupled to a 2219-T87 aluminum cathode. Duration of the EIS/PR and galvanic testing was 21 days and 24 h, respectively. The galvanic test results demonstrated a very high galvanic current between the aluminum cathode and both zinc-rich primer anodes (37.9 mA/cm2 and 23.7 mA/cm2 for the organic and inorganic primers, respectively). The PR results demonstrated a much higher corrosion rate of the zinc in the inorganic primer than in the organic primer, due primarily to the higher porosity in the former. Based on this investigation, the inorganic zinc-rich primer appears to provide superior galvanic protection and is recommended for additional study for application in the solid rocket booster aft skirt.

C. Barret, Launch Vehicle Flight Control Augmentation Using Smart Materials and Advanced Composites (CDDF 93-05), NASA TP-3535, Structures and Dynamics Laboratory, Science and Engineering Directorate. NASA Marshall Space Flight Center, AL 35812, February 1995, pp. 55.

Keywords: smart flight controls, flight control surfaces, launch vehicle control, advanced composites, smart materials, sensors, shape memory alloys, metal matrix composites, titanium matrix composites

Abstract: The Marshall Space Flight Center has a rich heritage of launch vehicles that have used aerodynamic surfaces for flight stability, such as the Saturn vehicles, and flight control, such as the Redstone. Recently, due to aft center-of-gravity locations on launch vehicles currently being studied, the need has arisen for the vehicle control augmentation that is provided by these flight controls. Aerodynamic flight control can also reduce engine gimbaling requirements, provide actuator failure protection, enhance crew safety, and increase vehicle reliability, and payload capability. In the Saturn era, NASA went to the Moon with 300 ft2 of aerodynamic surfaces on the Saturn V. Since those days, the wealth of smart materials and advanced composites that have been developed allow for the design of very lightweight, strong, and innovative launch vehicle flight control surfaces. This paper presents an overview of the advanced composites and smart materials that are directly applicable to launch vehicle control surfaces.

R.R. Kamenetzky, J.A. Vaughn, M.M. Finckenor and R.C. Linton, Evaluation of Thermal Control Coatings and Polymeric Materials Exposed to Ground Simulated Atomic Oxygen and Vacuum Ultraviolet Radiation, NASA TP-3595, Materials and Processes Laboratory, Science and Engineering Directorate. NASA Marshall Space Flight Center, AL 35812, December 1995, pp. 49.

Keywords: space environment, atomic oxygen, vacuum ultraviolet radiation, thermal control, anodized aluminum

Abstract: Numerous thermal control and polymeric samples with potential International Space Station applications were evaluated for atomic oxygen and vacuum ultraviolet radiation effects in the Princeton Plasma Physics Laboratory 5 eV Neutral Atomic Oxygen Facility and in the MSFC Atomic Oxygen Drift Tube System. Included in this study were samples of various anodized aluminum samples, ceramic paints, polymeric materials, and beta cloth, a Teflon»-impregnated fiberglass cloth. Aluminum anodizations tested were black duranodic, chromic acid anodize, and sulfuric acid anodize. Paint samples consisted of an inorganic glossy black paint and Z-93 white paint made with the original PS7 binder and the new K2130 binder. Polymeric samples evaluated included bulk Halar», bulk PEEK, and silverized FEP Teflon». Aluminized and nonaluminized Chemfab 250» beta cloth were also exposed. Samples were evaluated for changes in mass, thickness, solar absorptance, and infrared emittance. In addition to material effects, an investigation was made comparing diffuse reflectance/solar absorptance measurements made using a Beckman DK2 spectroreflectometer and like measurements made using an AZ Technology-developed laboratory portable spectroreflectometer.

    
Download Acrobat Reader!