Radiation enhanced precipitation of solute atoms in AlCu binary alloys

Abstract

AlCu binary alloys were irradiated with 16 MeV Au, 4.5 MeV Ni or 4.5 MeV Al ions at room temperature. Changes in surface hardness and the local atomic structure around Cu atoms were examined by using the Vickers hardness measurement and the EXAFS measurements, respectively. Some specimens were aged at 453K and Vickers hardness was measured. The computer simulation was also performed by using the rate equation method. The hardness of irradiated specimens increased much faster than that of the aged specimens and it became larger than the maximum value of the hardness for the aged specimens. The comparison of the experimental EXAFS result with that of FEFF simulation suggests that the ion irradiation produced small Cu precipitates in the specimens. The computer simulation visualized the growth process of Cu precipitates during the irradiation, and the result qualitatively corresponds to the experimental result.

Modification of Lattice Structures and Mechanical Properties of Metallic Materials by Energetic Ion Irradiation and Subsequent Thermal Treatments

“…The effect of the thermal aging, which was performed after the irradiation, was also investigated. The details of the experimental procedure are described in our previous reports [7][8][9]17,19].…”

“…First of all, the results for the binary alloys are discussed [19]. Figure 1 shows the Cu content dependence of the electrical resistivity for the pure Al and the Al-2%Cu and Al-4%Cu binary alloy specimens before the irradiation.…”

“…However, such studies for nuclear power plants and space developments have treated the negative effects of ion irradiation (so-called "radiation damage") on materials' properties. In our recent studies, we have positively used the energies deposited by energetic ion/electron irradiation for the modification of materials properties such as the mechanical properties [7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23], magnetic properties [24][25][26][27][28][29][30][31][32][33][34][35][36][37], and optical properties [38] of metallic and oxide materials.…”

“…In the following chapters, we will summarize our recent experimental results about the modification of the hardness by ion irradiations for two kinds of metallic materials; dilute aluminum alloys [7][8][9]17,19] and nickel-based intermetallic compounds [11,13,15,16,18,20,21]. The former is an example of the materials' modification through the irradiation-enhanced process, and the latter is that through the irradiation-induced process.…”