The Surface Behavior of a Binary Alloy During Production by Ion Implantation

ABSTRACTThin surface copper-nickel alloys were prepared by ion implantation at 90 keV. During the implantation of one pure element by the other the sputtered products were collected on catcher foils at different stages from the beginning of the implant through to the steady state configuration of the target surface. The collector foils and targets were analyzed to determine the behavior of the sputtering yields during implantation and for the change in surface composition at the selected fluence. The total sputtering yield for the target and the effective elemental sputtering yields for each component appear to be functions of the changing surface fractions, the self ion sputtering yield of the implanted species, and the elemental sputtering yield of the initial target species. A model relating these parameters is presented.

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Sputtering of Graphite by Hydrogen Isotopes in the Fusion Environment: A Molecular Dynamics Simulation Study

Journal of Nuclear Engineering and Radiation Science ◽

10.1115/1.4040495 ◽

2018 ◽

Vol 4 (4) ◽

Author(s):

Qiang Zhao ◽

Yang Li ◽

Zheng Zhang ◽

Xiaoping Ouyang

Keyword(s):

Molecular Dynamics ◽

Incident Energy ◽

Large Scale ◽

Incident Angle ◽

Hydrogen Isotopes ◽

Dynamics Simulation ◽

Calculation Results ◽

Sputtering Yield ◽

Increasing Temperature ◽

Sputtering Yields

The sputtering of graphite due to the bombardment of hydrogen isotopes is crucial to successfully using graphite in the fusion environment. In this work, we use molecular dynamics to simulate the sputtering using the large-scale atomic/molecular massively parallel simulator (lammps). The calculation results show that the peak values of the sputtering yield are between 25 eV and 50 eV. When the incident energy is greater than the energy corresponding to the peak value, a lower carbon sputtering yield is obtained. The temperature that is most likely to sputter is approximately 800 K for hydrogen, deuterium, and tritium. Below the 800 K, the sputtering yields increase with temperature. By contrast, above the 800 K, the yields decrease with increasing temperature. Under the same temperature and incident energy, the sputtering rate of tritium is greater than that of deuterium, which in turn is greater than that of hydrogen. When the incident energy is 25 eV, the sputtering yield at 300 K increases below an incident angle at 30 deg and remains steady after that.

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Hardening of Nickel Alloys by Ion Implantation of Titanium and Carbon

MRS Proceedings ◽

10.1557/proc-444-99 ◽

1996 ◽

Vol 444 ◽

Cited By ~ 7

Author(s):

S. M. Myers ◽

D. M. Follstaedt ◽

J. A. Knapp ◽

T. R. Christenson

Keyword(s):

Mechanical Properties ◽

Finite Element ◽

Surface Layer ◽

Ion Implantation ◽

Finite Element Modeling ◽

Yield Stress ◽

Nickel Alloys ◽

Element Modeling ◽

Order Of Magnitude ◽

Amorphous Surface

AbstractDual ion implantation of titanium and carbon was shown to produce an amorphous surface layer in annealed bulk nickel, in electroformed Ni, and in electroformed Ni7 5Fe 2 5. Diamond-tip nanoindentation coupled with finite-element modeling quantified the elastic and plastic mechanical properties of the implanted region. The amorphized matrix, with a thickness of about 100 nm, has a yield stress of approximately 6 GP and an intrinsic hardness near 16 GPa, exceeding by an order of magnitude the corresponding values for annealed bulk Ni. Implications for micro-electromechanical systems are discussed.

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