Characteristics of alumina particles in dispersion-strengthened copper alloys

Abstract

Two types of alumina dispersion-strengthened copper (ADSC) alloys were fabricated by a novel in-situ reactive synthesis (IRS) and a traditional internal oxidation (IO) process. The features of alumina dispersoids in these ADSC alloys were investigated by X-ray diffraction, scanning electron microscopy, and high-resolution transmission electron microscopy. It is found that nano-sized γ-Al₂O₃ particles of approximately 10 nm in diameter are homogeneously distributed in the IRS-ADSC composites. Meanwhile, larger-sized, mixed crystal structure alumina with rod-shaped morphology is embedded in the IO-ADSC alloy. The IRS-ADSC composites can obtain better mechanical and physical properties than the IO-ADSC composites; the tensile strength of the IRS-ADSC alloy can reach 570 MPa at room temperature, its electrical conductivity is 85% IACS, and the Rockwell hardness can reach 86 HRB.

Keywords

metallic matrix composites / alumina / copper / in-situ reactive synthesis / internal oxidation

References

[1] Rajkovic V, Bozic D, Devecerski A, Jovanovic MT. Characteristic of copper matrix simultaneously reinforced with nano- and micro-sized Al₂O₃ particles. Mater. Charact., 2012, 67, 129.

[2] Ďurišinová K, Ďurišin J, Orolínová M. Al₂O₃-dispersion strengthened nanocrystalline copper. Powder Metall. Prog., 2006, 6(2): 75

[3] Jena PK, Brocchi EA, Solórzano IG, Motta MS. Identification of a third phase in Cu-Al₂O₃ nanocomposites prepared by chemical routes. Mater. Sci. Eng. A, 2004, 371(1–2): 72.

[4] Espinoza RA, Palma RH, Sepúlveda AO, Fuenzalida V, Solórzano G, Craievich A, Smith DJ, Fujita T, López M. Microstructural characterization of dispersion-strengthened Cu-Ti-Al alloys obtained by reaction milling. Mater. Sci. Eng. A, 2007, 454–455, 183.

[5] Tian BH, Liu P, Song KX, Li Y, Liu Y, Ren FZ, Su JH. Microstructure and properties at elevated temperature of a nano-Al₂O₃ particles dispersion-strengthened copper base composite. Mater. Sci. Eng. A, 2006, 435–436, 705.

[6] Shehata F, Fathy A, Abdelhameed M, Moustafa SF. Preparation and properties of Al₂O₃ nanoparticle reinforced copper matrix composites by in situ processing. Mater. Des., 2009, 30(7): 2756.

[7] Stobrawa JP, Rdzawski ZM. Dispersion-strengthened nanocrystalline copper. J. Achiev. Mater. Manuf. Eng., 2007, 24(2): 35

[8] Han SL, Qin XD, Cai YX, Luo K, Xie HW, Li DR. Properties and fabrication of alumina dispersion strengthened copper alloy with high softening temperature. Mater. Sci. Forum, 2013, 749, 425.

[9] Wu R, Zhang DW, Sun J, Ren FZ, He QC. Preparation of Al₂O₃/Cu composites by internal oxidation in Cu-Al alloy sheet processing. Adv. Mater. Res., 2013, 602–604, 2034

[10] Zhang XH, Lin CG, Cui S, Li ZD. Microstructure and properties of Al₂O₃ dispersion-strengthened copper fabricated by reactive synthesis process. Rare Met., 2014, 33(2): 191.

[11] Zhang XH, Lin CG, Cui S, Li ZD, Hu XK. Microstructure of Al₂O₃-dispersion strengthened copper prepared by SPS. Trans. Mater. Heat Treat., 2013, 34(11): 1

[12] Valibeygloo N, Khosroshahi RA, Mousavian RT. Microstructural and mechanical properties of Al-4.5wt%Cu reinforced with alumina nanoparticles by stir casting method. Int. J. Miner. Metall. Mater., 2013, 20(10): 978.

[13] Nie JH, Jia CC, Jia X, Li Y, Zhang YF, Liang XB. Fabrication and thermal conductivity of copper matrix composites reinforced by tungsten-coated carbon nanotubes. Int. J. Miner. Metall. Mater., 2012, 19(5): 446.

[14] Kudashov DV, Baum H, Martin U, Heilmaier M, Oettel H. Microstructure and room temperature hardening of ultra-fine-grained oxide-dispersion strengthened copper prepared by cryomilling. Mater. Sci. Eng. A, 2004, 387–389, 768.

[15] Palma HR, Sepúlveda OA. Contamination effects on precipitation hardening of Cu-alumina alloys, prepared by mechanical alloying. Mater. Sci. Forum, 2003, 416–418, 162.

[16] Yan P, Lin CG, Cui S, Lu YJ, Zhou ZL, Li ZD. Microstructural features and properties of high-hardness and heat-resistant dispersion strengthened copper by reaction milling. J. Wuhan Univ. Technol. Mater. Sci. Ed., 2011, 26(5): 902.

[17] Cheng JY, Wang MP, Cao JG, Zhao XL, Guo MX. Influence of nano-scaled dispersed second phase on substructure of deformed dispersion strengthened copper alloy. J. Cent. South Univ. Technol., 2005, 12(1): 50.