Precipitation strengthened high strength, high conductivity copper-chromium-niobium alloys produced by chill block melt spinning

There are many potential applications for materials that possess a combination of high strength, high conductivity, and good long term stability at elevated temperatures.;In an effort to achieve this combination of properties a 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 for testing. The desire was to produce a supersaturated Cu-Cr-Nb solid solution from which the high melting point intermetallic compound Cr;The results show that the materials possess electrical conductivities in excess of 90% that of pure Cu at 200;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;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;TEM of the as-melt spun samples revealed that the Cr...