CENTRO DE INVESTIGACIONES EN FISICA E INGENIERIA DEL CENTRO DE LA PROVINCIA DE BUENOS AIRES
Unidad Ejecutora - UE
Behaviour of nitrided and carburised AISI 904L stainless steels under severe light ion beam irradiation by plasma focus
J. GARCÍA MOLLEJA, ; M. MILANESE ; J. BÜRGI; M. PICCOLI; B.J. GÓMEZ; R. MOROSO; J.J. NIEDBALSKI; E. BEMPORAD ; J. FEUGEAS
APPLIED SURFACE SCIENCE
ELSEVIER SCIENCE BV
Lugar: Amsterdam; Año: 2015
Superaustenitic stainless steels have become of growing interest in industrial and technological fields, but there is not a complete understanding on their fundamental properties and their performances. For this paper, AISI 904L superaustenitic samples were nitrided and carburized in order to study the expanded austenite stability under severe deuterium and helium ion bombardment. Surface treatments were conducted using pulsed plasma glow discharges in a low pressure atmosphere and a dense plasma focus device was used to irradiate the samples. Characterization techniques used were focused ion beam/scanning electron microscopy, energydispersive Xray spectroscopy and grazing incidence Xray diffraction. Our results showed in carburized samples lattice expansion growth with the time treatment but in nitrided samples an expanded austenite reduction with time treatment was observed due to the formation of nitride nanoagglomerates. Moreover, this ion impingement provoked surface melting and a severe collision cascade and a damaged bead located under the craters composed solely of minor alloying atoms. Furthermore, nitrided samples were more stable following ion bombardment than the carburized ones. When helium ions were used the loss of expansion (triggered by diffusion processes of N or C to deeper regions) was more pronounced in the expanded austenite but when deuterium ions were used to bombard the sample there was a crystallite development of stressed austenite which provoked a diffraction peak arousal at 43.3°.