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E-15798 Cover NASA/TM—2007-214663 Comparison of GRCop-84 to Other High Thermal Conductive Cu Alloys Henry C. de Groh III and David L. Ellis Glenn Research Center, Cleveland, Ohio William S. Loewenthal Ohio Aerospace Institute, Brook Park, Ohio February 2007 NASA STI Program . in Profile Since its founding, NASA has been dedicated to the • CONFERENCE PUBLICATION. Collected advancement of aeronautics and space science. The papers from scientific and technical NASA Scientific and Technical Information (STI) conferences, symposia, seminars, or other program plays a key part in helping NASA maintain meetings sponsored or cosponsored by NASA. this important role. • SPECIAL PUBLICATION. Scientific, The NASA STI Program operates under the auspices technical, or historical information from of the Agency Chief Information Officer. It collects, NASA programs, projects, and missions, often organizes, provides for archiving, and disseminates concerned with subjects having substantial NASA’s STI. The NASA STI program provides access public interest. to the NASA Aeronautics and Space Database and its public interface, the NASA Technical Reports Server, • TECHNICAL TRANSLATION. English- thus providing one of the largest collections of language translations of foreign scientific and aeronautical and space science STI in the world. technical material pertinent to NASA’s mission. Results are published in both non-NASA channels and by NASA in the NASA STI Report Series, which Specialized services also include creating custom includes the following report types: thesauri, building customized databases, organizing and publishing research results. • TECHNICAL PUBLICATION. Reports of completed research or a major significant phase For more information about the NASA STI of research that present the results of NASA program, see the following: programs and include extensive data or theoretical analysis. Includes compilations of significant • Access the NASA STI program home page at scientific and technical data and information http://www.sti.nasa.gov deemed to be of continuing reference value. NASA counterpart of peer-reviewed formal • E-mail your question via the Internet to professional papers but has less stringent [email protected] limitations on manuscript length and extent of graphic presentations. • Fax your question to the NASA STI Help Desk at 301–621–0134 • TECHNICAL MEMORANDUM. Scientific and technical findings that are preliminary or • Telephone the NASA STI Help Desk at of specialized interest, e.g., quick release 301–621–0390 reports, working papers, and bibliographies that contain minimal annotation. Does not contain • Write to: extensive analysis. NASA Center for AeroSpace Information (CASI) 7115 Standard Drive • CONTRACTOR REPORT. Scientific and Hanover, MD 21076–1320 technical findings by NASA-sponsored contractors and grantees. NASA/TM—2007-214663 Comparison of GRCop-84 to Other High Thermal Conductive Cu Alloys Henry C. de Groh III and David L. Ellis Glenn Research Center, Cleveland, Ohio William S. Loewenthal Ohio Aerospace Institute, Brook Park, Ohio National Aeronautics and Space Administration Glenn Research Center Cleveland, Ohio 44135 February 2007 Acknowledgments We would like to praise and acknowledge the dedicated support of our technicians and machine shop personnel: John Zoha, Sharon Thomas, Bill Armstrong, John Juhas, Adrienne Veverka, Ronald Phillips, Dave Brinkman, Aldo Panzanella, and Tim Ubienski; as well as our furnace/heat treat engineer Mark Jaster. Their support has enabled timely progress on this effort. This report is a formal draft or working paper, intended to solicit comments and ideas from a technical peer group. This report contains preliminary findings, subject to revision as analysis proceeds. Trade names and trademarks are used in this report for identification only. Their usage does not constitute an official endorsement, either expressed or implied, by the National Aeronautics and Space Administration. Level of Review: This material has been technically reviewed by technical management. Available from NASA Center for Aerospace Information National Technical Information Service 7115 Standard Drive 5285 Port Royal Road Hanover, MD 21076–1320 Springfield, VA 22161 Available electronically at http://gltrs.grc.nasa.gov Contents Abstract............................................................................................................................................1 I. Introduction ..................................................................................................................................1 II. Test Procedures ...........................................................................................................................4 A. Tensile and Creep Procedures........................................................................................... 4 B. Thermal Expansion Procedures......................................................................................... 5 C. Strength Recovery Test for Cu-1Cr-0.1Zr ........................................................................ 5 III. Test Results................................................................................................................................6 A. Microstructures ................................................................................................................. 6 B. Tensile and Compression Tests......................................................................................... 7 C. Cooling Rate Effects on Hardenability of Cu-1Cr-0.1Zr.................................................. 8 D. Creep Tests........................................................................................................................ 8 E. Thermal Expansion............................................................................................................9 IV. Discussion..................................................................................................................................9 A. Comparison of Properties ................................................................................................. 9 B. Microstructure-Property Relations.................................................................................. 10 C. Property Implications on Alloy Selection....................................................................... 10 D. Future Work.................................................................................................................... 11 V. Summary and Conclusions........................................................................................................11 Tables.............................................................................................................................................12 Table 1. Composition of Cu alloys in weight percent. .........................................................12 Table 2. Simulated braze heat treatment...............................................................................12 Table 3. Ultimate Tensile Stress (UTS) in units of MPa for GRCop-84, AMZIRC, GlidCop Al-15, Cu-1Cr-0.1Zr, and Cu-0.9Cr alloys at various test temperatures; numbers in the table are averages of multiple tests, five tests at each temperature for GRCop-84, most others are the average of two tests..........................................13 Table 4. Yield Stress (YS) in units of MPa defined as the stress at 0.2% off-set strain, for GRCop-84, AMZIRC, GlidCop Al-15, Cu-1Cr-0.1Zr, and Cu-0.9Cr alloys at various test temperatures; numbers in the table are averages of multiple tests, five tests at each temperature for GRCop-84, most others are the average of two tests. ..........................................................................................................................13 Table 5. Elongation, in units of %, defined as the change in gage length divided by the initial gage length times 100%, for GRCop-84, AMZIRC, GlidCop Al-15, and Cu-1Cr-0.1Zr alloys at various test temperatures; numbers in the table are averages of multiple tests, five tests at each temperature for GRCop-84, most others are the average of two tests............................................................................14 Table 6. Reduction in area (R/A) in units %, defined as the change in cross-sectional area divided by the initial area times 100%, for GRCop-84, AMZIRC, GlidCop Al-15, and Cu-1Cr-0.1Zr alloys at various test temperatures; numbers in the table are averages of multiple tests, five tests at each temperature for GRCop- 84, most others are the average of two tests. ............................................................14 NASA/TM—2007-214663 iii Table 7. Compressive Yield Strength, in units MPa, defined as the compressive stress at 0.2% off-set strain, for GRCop-84, AMZIRC, GlidCop Al-15, Cu-1Cr-0.1Zr, and Cu-0.9Cr alloys at various test temperatures; numbers in the table are averages of multiple tests, two or three tests at each temperature for GRCop-84, all of the values for the other alloys are the average of two tests.............................15 Table 8. Step Loaded, Creep Strain Rates at various temperatures, in units of strain/second, with 5 hours at each stress listed, for up to 20 steps, or failure. Creep, or strain rate, was defined as the slope of the time-strain data at the inflection point between primary and tertiary creep.................................................16 Table 9. Power function constants for step loaded, secondary steady state creep; creep rate power functions
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