Electrical Performance of Bulk Al-ZrB_2 Nanocomposites from 2 K to 300 K

摘要

Electrical properties are of significance for metals/alloys and their applications. While nanoparticles can enhance mechanical performance of metals/alloys, there is a strong need to understand how nanoparticles affect their electric behavior at various temperatures. In this study, ZrB_2 nanoparticles were synthesized in situ to cast bulk Al-ZrB_2 samples for electric characterizations. The electrical conductivity, electron mobility, and electron concentration of Al-3 vol.% ZrB_2 were measured in the temperature range from 2 K to 300 K. The effects of in situ ZrB_2 nanoparticles on the Al matrix were systematically studied in terms of its compositions, morphologies, grain sizes, and nanophase sizes. It is discovered the Al-ZrB_2 interfaces play a key role in tuning structural and electrical performances. This mechanism is important to better understand the electron behaviors in Al alloys containing in situ nanoparticles. The in situ fabrication and electrical characterization methods can be readily applied to other metallic nanocomposites.