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Design of exceptionally strong and conductive Cu alloys beyond the conventional speculation via the interfacial energy-controlled dispersion of γ-Al2O3 nanoparticles.

Han SZ, Kim KH, Kang J, Joh H, Kim SM, Ahn JH, Lee J, Lim SH, Han B - Sci Rep (2015)

Bottom Line: In this paper, we demonstrate that these contradictory material properties can be improved simultaneously if the interfacial energies of heterogeneous interfaces are carefully controlled.We uniformly disperse γ-Al2O3 nanoparticles over Cu matrix, and then we controlled atomic level morphology of the interface γ-Al2O3//Cu by adding Ti solutes.Furthermore, the Ti removes impurities (O and Al) in the Cu matrix by forming oxides leading to recovery of the electrical conductivity of pure Cu.

View Article: PubMed Central - PubMed

Affiliation: Structural Materials Division, Korea Institute of Materials Science, Changwon, 51508, Korea.

ABSTRACT
The development of Cu-based alloys with high-mechanical properties (strength, ductility) and electrical conductivity plays a key role over a wide range of industrial applications. Successful design of the materials, however, has been rare due to the improvement of mutually exclusive properties as conventionally speculated. In this paper, we demonstrate that these contradictory material properties can be improved simultaneously if the interfacial energies of heterogeneous interfaces are carefully controlled. We uniformly disperse γ-Al2O3 nanoparticles over Cu matrix, and then we controlled atomic level morphology of the interface γ-Al2O3//Cu by adding Ti solutes. It is shown that the Ti dramatically drives the interfacial phase transformation from very irregular to homogeneous spherical morphologies resulting in substantial enhancement of the mechanical property of Cu matrix. Furthermore, the Ti removes impurities (O and Al) in the Cu matrix by forming oxides leading to recovery of the electrical conductivity of pure Cu. We validate experimental results using TEM and EDX combined with first-principles density functional theory (DFT) calculations, which all consistently poise that our materials are suitable for industrial applications.

No MeSH data available.


Related in: MedlinePlus

Schematic flow diagram showing the process in (a) and in (b) the internal oxidation method to design Al2O3 nanoparticle dispersed Cu alloys.
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f1: Schematic flow diagram showing the process in (a) and in (b) the internal oxidation method to design Al2O3 nanoparticle dispersed Cu alloys.

Mentions: The 99.9 % pure Cu, Al and Ti were used to prepare Cu-Al and Cu-Al-Ti alloy ingots by atmospheric induction melting and permanent mold casting. We designed four different Cu alloys as a function of the relative composition of Al/Ti and with/without internal oxidation (Table 1). The ingots were hot rolled in the uniaxial direction at 980 °C after being held for one hour. The surface of each plate was scalped to an approximate thickness of 0.5 mm and cold rolled to a 75 % thickness reduction. The sheets of the cold-rolled plates were oxidized at 980 °C for two or four hours at ambient atmosphere. Oxides (Cu2O) on the oxidized sheets was removed by wire brushing and ultrasonic cleaning. Figure 1 depicts a schematic flow diagram of the overall fabrication of the oxide-dispersed Cu alloy composite. The wire-type specimen was fabricated by drawing at room temperature after oxidation at 980 °C for 1 hour.


Design of exceptionally strong and conductive Cu alloys beyond the conventional speculation via the interfacial energy-controlled dispersion of γ-Al2O3 nanoparticles.

Han SZ, Kim KH, Kang J, Joh H, Kim SM, Ahn JH, Lee J, Lim SH, Han B - Sci Rep (2015)

Schematic flow diagram showing the process in (a) and in (b) the internal oxidation method to design Al2O3 nanoparticle dispersed Cu alloys.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4663622&req=5

f1: Schematic flow diagram showing the process in (a) and in (b) the internal oxidation method to design Al2O3 nanoparticle dispersed Cu alloys.
Mentions: The 99.9 % pure Cu, Al and Ti were used to prepare Cu-Al and Cu-Al-Ti alloy ingots by atmospheric induction melting and permanent mold casting. We designed four different Cu alloys as a function of the relative composition of Al/Ti and with/without internal oxidation (Table 1). The ingots were hot rolled in the uniaxial direction at 980 °C after being held for one hour. The surface of each plate was scalped to an approximate thickness of 0.5 mm and cold rolled to a 75 % thickness reduction. The sheets of the cold-rolled plates were oxidized at 980 °C for two or four hours at ambient atmosphere. Oxides (Cu2O) on the oxidized sheets was removed by wire brushing and ultrasonic cleaning. Figure 1 depicts a schematic flow diagram of the overall fabrication of the oxide-dispersed Cu alloy composite. The wire-type specimen was fabricated by drawing at room temperature after oxidation at 980 °C for 1 hour.

Bottom Line: In this paper, we demonstrate that these contradictory material properties can be improved simultaneously if the interfacial energies of heterogeneous interfaces are carefully controlled.We uniformly disperse γ-Al2O3 nanoparticles over Cu matrix, and then we controlled atomic level morphology of the interface γ-Al2O3//Cu by adding Ti solutes.Furthermore, the Ti removes impurities (O and Al) in the Cu matrix by forming oxides leading to recovery of the electrical conductivity of pure Cu.

View Article: PubMed Central - PubMed

Affiliation: Structural Materials Division, Korea Institute of Materials Science, Changwon, 51508, Korea.

ABSTRACT
The development of Cu-based alloys with high-mechanical properties (strength, ductility) and electrical conductivity plays a key role over a wide range of industrial applications. Successful design of the materials, however, has been rare due to the improvement of mutually exclusive properties as conventionally speculated. In this paper, we demonstrate that these contradictory material properties can be improved simultaneously if the interfacial energies of heterogeneous interfaces are carefully controlled. We uniformly disperse γ-Al2O3 nanoparticles over Cu matrix, and then we controlled atomic level morphology of the interface γ-Al2O3//Cu by adding Ti solutes. It is shown that the Ti dramatically drives the interfacial phase transformation from very irregular to homogeneous spherical morphologies resulting in substantial enhancement of the mechanical property of Cu matrix. Furthermore, the Ti removes impurities (O and Al) in the Cu matrix by forming oxides leading to recovery of the electrical conductivity of pure Cu. We validate experimental results using TEM and EDX combined with first-principles density functional theory (DFT) calculations, which all consistently poise that our materials are suitable for industrial applications.

No MeSH data available.


Related in: MedlinePlus