Nanostructured surfaces

Thermal helium desorption of implanted in austenitic stainless steel 18Cr10NiTi. Effects dose and temperature implantation
O. Morozov, V.I. Zhurba, O.V. Mats., V.O. Progolaeva
NSC-Kharkiv Institute of Physics and Technology of the NAS of Ukraine.
1, Akademichna St., Kharkiv-61108, Ukraine.
E-mail: morozov@kipt.kharkov.ua

Helium thermal desorption spectra were investigated on the samples of austenitic steel 18Cr10NiTi pre-implanted with 24 keV helium ions at current density 5 μA/cm2 in the dose range from 5 × 1016 to 4 × 1018 He/cm2 at the sample temperature Tirr ~ 100 K, RT and 600 K.
The spectrum of helium thermodesorption from the samples exposed to doses ~ 5 × 1016 He/cm2 represents the temperature-scale smeared region of helium desorption with maxima in the temperature ~1470 K.
The increase in a dose of the implanted helium is accompanied by advancement of a spectrum of allocation of helium in a direction of fall of temperature. For a dose 4×1016 Не/см2 the spectrum helium thermodesorption represents to the area washed away on a temperature scale desorption with badly divided peaks in a range of temperatures 1000 – 1400 K.
At the further increase in a dose of the implanted helium there is a qualitative change of a spectrum thermodesorption the helium, shown in formation of peak to maximum temperature at Tm ~ 1000 K. The further increase in a dose of the implanted helium leads to growth of intensity of this peak of a spectrum thermodesorption and it becomes prevailing.
At doses above 1×1018 He/cm2 (at temperatures Tirr ~ 100 K, RT) is formed low temperature region helium desorption in a kind washed away on a temperature scale of desorption region with a maximum at Tm~450 K. The quantity of the implanted helium is decreases.
Proceeding from representation that atoms of helium in a crystal lattice of a steel form vacancy – helium complexes, peak with temperature of a maximum ~1000 K corresponds to temperature of disintegration of such complexes. Thus the quantity of atoms of helium in a complex is strictly defined. Further energy of activation desorption helium will be calculated, the analysis of the received results of research is offered.