NASA LogoNTRSNTRS - NASA Technical Reports ServerSearchmore_vertCollectionsAboutNewsHelpLogin Back to ResultsPrecipitation strengthened high strength, high conductivity Cu-Cr-Nb alloys produced by chill block melt spinningA series of Cu-based alloys containing 2 to 10 a/o Cr and 1 to 5 a/o Nb were produced by chill block melt spinning (CBMS). The melt spun ribbons were consolidated and hot rolled to sheet to produce a supersaturated Cu-Cr-Nb solid solution from which the high melting point intermetallic compound Cr2Nb could be precipitated to strengthen the Cu matrix. The results show that the materials possess electrical conductivities in excess of 90 percent that of pure Cu at 200 C and above. The strengths of the Cu-Cr-Nb alloys were much greater than Cu, Cu-0.6 Cr, NARloy-A, and NARloy-Z in the as-melt spun condition. The strengths of the consolidated materials were less than Cu-Cr and Cu-Cr-Zr below 500 C and 600 C respectively, but were significantly better above these temperatures. The strengths of the consolidated materials were greater than NARloy-Z, at all temperatures. The GLIDCOP possessed similar strength levels up to 750 C when the strength of the Cu-Cr-Nb alloys begins to degrade. The long term stability of the Cu-Cr-Nb alloys was measured by the microhardness of aged samples and the growth of precipitates. The microhardness measurements indicate that the alloys overage rapidly, but do not suffer much loss in strength between 10 and 100 hours which confirms the results of the electrical resistivity measurements taken during the aging of the alloys at 500 C. The loss in strength from peak strength levels is significant, but the strength remains exceptionally good. Transmission electron microscopy (TEM) of the as-melt spun samples revealed that Cr2Nb precipitates formed in the liquid Cu during the chill block melt spinning, indicating a very strong driving force for the formation of the precipitates. The TEM of the aged and consolidated materials indicates that the precipitates coarsen considerably, but remain in the submicron range.Document ID19900002537Acquisition SourceLegacy CDMSDocument TypeThesis/DissertationAuthorsEllis, David L.*(Case Western Reserve Univ. Cleveland, OH, United States)*Michal, Gary M.*(Case Western Reserve Univ. Cleveland, OH, United States)*Date AcquiredSeptember 6, 2013Publication DateSeptember 1, 1989Subject CategoryMetallic MaterialsReport/Patent NumberNAS 1.26:185144NASA-CR-185144Accession Number90N11853Funding Number(s)CONTRACT_GRANT: NGT-50087PROJECT: RTOP 553-13-00Distribution LimitsPublicCopyrightWork of the US Gov. Public Use Permitted.Available DownloadsNameType19900002537.pdfSTIcloud_downloadcontent_copyvisibilityRelated RecordsThere are no records associated with this record.visibility_offNo Preview Available
 No Fear Act | Freedom of Information Act | Office of the Inspector General | Agency Financial ReportsNASA Web Privacy Policy and Important Notices | NASA Guidelines for Quality of InformationDisclaimers, Copyright, Terms of Use | Accessibility | NASA OCIO | USA.gov | NASA.govContact Us | Site MapSTI LogoNASA Official: JoAnne R. Calhoun Site Curator: STI Compliance and Distribution Services Last Modified: September 12, 2024