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Using X-ray diffraction analysis, the effect of Ar+ ions with an energy of 15−20 keV (at ion current densities of 100−300 μA/cm2) on the microstructure, the level of internal microstresses and the texture of cold rolled ribbons of alloy Ni – 13.9 wt.% W is studied. It is found out that short-term irradiation of 80 μm thick ribbons with a fluence of 3.1·1016 cm–2 (for 50 s) at temperatures T ≤ 370°C and T = 630°C leads to a decrease in microstresses in their entire volume, while the original texture is retained. With an increase in the fluence to 9.7·1017 cm–2 at T = 630°C, the texture changes from (220) to (200). Changes in microstresses and texture on the irradiated and non-irradiated sides of 80-μm-thick ribbons are comparable to each other, despite the fact that the projected range of Ar+ ions with an energy of 15−20 keV in the alloy is only ~7 nm. It is known that annealing of such ribbons in an oven (700°C, 30 min) does not cause their recrystallization. At 850°C, the microstresses are relieved and the texture dramatically changes from (220) to (200) both as a result of annealing in a furnace (15 s) and as a result of irradiation with a fluence of 3.2·1016 cm–2 for 17 s, but the effect of stress removal in the course of furnace annealing is 3 times lower than that of irradiation. Thus, the following facts have been established: 1) the occurrence of recrystallization processes in the alloy under study during irradiation at a temperature lower than the temperature of the onset of thermally activated recrystallization and 2) a higher rate of microstress drop (and to lower values) in the course of irradiation than during furnace annealing. This indicates a significant role of nanoscale radiation-dynamic effects at the cascade-forming irradiation of metastable media. [ABSTRACT FROM AUTHOR]

Using electron microscopy it was found that irradiation of clad cold-worked specimens made of commercial aluminium-lithium alloy 1441 by the Ar + ions of energy 40 keV at low doses of irradiation (1015 cm−2, irradiation time 1 s, T < 70 °C) and ion-current density of about 100 µA/cm2 results in the transformation of the cellular structure formed in the alloy under deformation. As the dose of irradiation is increased up to 1016 cm−2, a transition from a cellular to a subgrain structure close to a polygonal one is observed. The efficiency of the process is increased with ion-current density. Furthermore, under ion irradiation at increased ion-current densities, the β′( Al 3 Zr) and Al 8 Fe 2 Si particles present in the deformed alloy dissolve, and disperse particles of a new Al 2 LiMg phase of platelet shape are formed. The changes in the dislocation structure and phase composition in alloy 1441 are observed several seconds after irradiation not only in the surface layer adjacent to the ion incorporation band but also through the thickness of the specimen tens of thousands times greater than ion projective ranges. [ABSTRACT FROM AUTHOR]