| Title |
Research papers / Mechanical Behaviors : Microstructure and Mechanical Properties of Oxide Dispersion Strengthened Cu-Al2O3 Alloys Fabricated by Internal Oxidation |
| Authors |
이종상(Jong Sang Lee),김용찬(Yong Chan Kim),이성학(Sung Hak Lee),안상호(Sang Ho Ahn),김낙준(Nack J. Kim) |
| ISSN |
1738-8228(ISSN), 2288-8241(eISSN) |
| Abstract |
The present study is concerned with microstructure and mechanical properties of oxide dispersion strengthened(ODS) Cu-Al_2O_3 alloys fabricated by internal oxidation. Atomized Cu-Al powders mixed with Cu_2O oxidant powders were internally oxidized and then hot-extruded to form ODS Cu-Al_2O_3 alloys without defects. Here, a 30% excessive amount of oxidant powders over a stoichiometrically calculated amount was required in order to sufficiently oxidize Cu-Al powders. In the extruded Cu-Al_2O_3 alloys, very fine Al_2O_3 dispersoids of 10 nm in diameter were homogeneously distributed inside Cu grains of 1 ㎛ in size. Yield and tensile strengths increased with increasing volume fraction of Al_2O_3 dispersoids, while elongation and electrical conductivity decreased, and all the properties of the Cu-Al_2O_3 alloys were sufficiently satisfied with the required properties for applications. To understand the mechanism responsible for the improvement of yield strength of the ODS Cu-Al_2O_3 alloys, yield strength was analyzed using the Orowan mechanism, which was fairly consistent with the experimental results. |