The electrical properties of nanocrystalline Cu-Al2O3

Abstract

Nanocrystalline (nc) Cu powders with Al2O3 dispersoid (1-5 vol.% Al2O3) were prepared by combination of phase transformations with intensive milling and the following consolidation by pressing, sintering and hot extrusion. The electrical properties of the composites were analysed in relation to their microstructure and strength. The main contribution to the electrical resistivity was attributed to the grain/crystallite size of Cu matrix. The fraction of Fe impurities dissolved within the Cu matrix and the amount of Al2O3 particles in the Cu matrix affected the electrical resistivity remarkably. The optimal combination of electrical and strength properties can be achieved by cut-down of Al2O3 content and by optimization of dispersoid distribution in the matrix.K e y w o r d s : nanocrystalline Cu-Al2O3 alloys, dispersion strengthening, electrical properties, thermal stability

Archives of Metallurgy and Materials

“…furthermore, with increasing ceramic concentration, the effect of pores or cracks in the vicinity of the interface between the metal matrix and ceramic additive can be increased. The presence of these voids or cracks can also contribute to the difference between the theoretical and measured electrical conductivities [19][20]. was obtained when 1.2 wt.% of zirconia was added.…”

Development of novel ultrafine grain cu metal matrix composites reinforced with Ti-Cu-Co-M (M: Ni, Zr) amorphous-nanocrystalline powder

“…Such Cu-based metal matrix composites have been extensively studied in recent years due to attained better properties than pure copper [17,18,19,20]. Cu-based composites with nano-Al 2 O 3 [21,22,23,24] are materials developed for wide range of applications. Cu-composites with graphene [25,26,27] and C-nanotubes [28] have been extensively investigated also.…”

“…%) and the consolidation process (hot-pressing) on the microstructure, mechanical and electrical properties. Electrical resistance of MMCs is expected to increase by the reinforcements [22,23], a negative effect of additives. To study the variation in electrical resistance the application of at least two additive compositions is required.…”