Effect of the energy density deposited by a 3.66-MeV Nickel ion beam on the sputtering yield of a hypereutectic alloy

Abstract

Dilute alloys of Ni–Si binary system have been used as base material to study microstructural changes caused by irradiation in complex alloys. However, non-dilute Ni–Si alloys, which are themselves also important for high-temperature applications, have been little studied under irradiation. In this paper, the behavior of a hypereutectic alloy, Ni22at.%Si, under severe irradiation conditions is evaluated, to determine changes induced on the surface and elucidate the possible mechanisms that promote them. As a result of irradiating this alloy with Ni ions of 3.66 MeV at 650°C and an incidence perpendicular to the surface, the presence of nanohills is detected, as well as groove patterns and craters, which formation is attributed to different sputtering mechanisms. To characterize these changes, optical, scanning electron and atomic force microscopies were used. Comparing the experimental findings with some of the most important physical models of sputtering, it was concluded that such changes to the surface microstructure strongly depend on the amount of energy deposited during irradiation and on how it is distributed in the microstructural features developed in the alloy during its manufacture. Moreover, when the radiation dose was changed to evaluate the sputtering yield as a dose function, it was detected as geometric sputtering mechanism.

KEYWORDS:

• Surface modification
• ion beam irradiation
• nanogrooves
• nanocraters
• preferential sputtering

Acknowledgements

Thanks are due to the staff of the IFF-FZ-Julich accelerator, Prof. Dr. H. Ullmaier and W. Kesternich for their support in the irradiation experiments.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Notes on contributors

Carlos Alberto Camacho-Olguín

Professor Carlos Alberto Camacho-Olguín, his field of research is solid state physics, mainly nanotechnologies and interaction of materials with radiation.

Roberto A. Rodriguez-Diaz

PhD Roberto A. Rodriguez-Diaz, his field of development is materials engineering.

Arturo García-Borquez

PhD Arturo García-Borquez, his field of development is solid state physics, with extensive experience as a microscopist, he handles the following SEM, TEM and MFA techniques.

Héctor Cruz-Mejía

PhD Héctor Cruz-Mejía, specialist in solidification of non-ferrous alloys.

Rosalinda Camacho-Olguín

Professor Rosalinda Camacho-Olguín, currently developing her doctoral thesis in nanotechnologies, retired professor.