Effect of Preliminary Irradiation of 321 Steel Substrates with High-Intense Pulsed Ion Beams on Scratch Test Results of Subsequently Deposited AlN Coatings

Abstract

The paper presents the effect of irradiation of 321 steel substrates with a high-intense pulsed ion beam (HIPIB) on changes in functional properties of the surface layers and tribological characteristics of AlN coatings subsequently deposited above by the reactive magnetron sputtering method. The morphology of the modified surface layers, their microhardness and free surface energy levels are presented for different HIPIB energy densities. HIPIB irradiation of the substrates caused variations in the results of scratch tests combined with the acoustic emission signal processing. Their analysis has enabled concluding that the crack initiation threshold could be at least doubled for the studied coating/substrate system due to preliminary HIPIB irradiation. Finally, the obtained data were discussed, and future research directions were proposed.

Study of the Application Efficiency of Irradiation with Heavy Ions to Increase the Helium Swelling Resistance of BeO Ceramics

“…By analyzing the obtained data on reduction of helium-swelling value and comparing them with the literature data [15][16][17]19,20] on other methods of modification and protection against helium embrittlement, the following conclusions can be drawn. As is known from References [15][16][17], one method of increasing swelling resistance and subsequent structure degradation is the method of high-precision pulsed irradiation with electrons and ions.…”

“…By analyzing the obtained data on reduction of helium-swelling value and comparing them with the literature data [15][16][17]19,20] on other methods of modification and protection against helium embrittlement, the following conclusions can be drawn. As is known from References [15][16][17], one method of increasing swelling resistance and subsequent structure degradation is the method of high-precision pulsed irradiation with electrons and ions. This process is based on the effect of remelting the near-surface layer due to the powerful influence of a pulsed beam of electrons or ions with a high current density (in some cases, the current is µA or mA) in a very short period of time.…”

“…This hypothesis is based on the assumption that dislocation defects isolated from each other due to small fluences of irradiation with heavy ions will create additional obstacles to migrating helium ions, thereby preventing them from agglomeration into large gas-filled bubbles. The basis for this hypothesis was a number of experimental works [14][15][16][17][18][19][20] aimed at studying the applicability of ionizing radiation to increase the radiation resistance of materials, as well as studying the mechanisms of radiation hardening of the near-surface layer of ceramics, steels, and multilayer coatings. Therefore, for example, in a number of works, the effect of radiation hardening at irradiation with high-precision pulse beams of near-surface layers of refractory materials and ceramics is considered [14][15][16][17][18][19][20][21][22].…”

“…The basis for this hypothesis was a number of experimental works [14][15][16][17][18][19][20] aimed at studying the applicability of ionizing radiation to increase the radiation resistance of materials, as well as studying the mechanisms of radiation hardening of the near-surface layer of ceramics, steels, and multilayer coatings. Therefore, for example, in a number of works, the effect of radiation hardening at irradiation with high-precision pulse beams of near-surface layers of refractory materials and ceramics is considered [14][15][16][17][18][19][20][21][22]. The authors of these works call the main hardening mechanism changes in dislocation density and amorphization processes, followed by the formation of amorphous inclusions in the structure of the near-surface radiation-modified layer.…”

“…Thus, by analyzing the literature data of previously carried out experimental works [14][15][16][17][18][19][20][21][22][23][24][25], one can make an assumption about the possible positive effect of radiation hardening of the near-surface layers of irradiated materials that consists in changing the dislocation density and defect structure of the layer. These changes can play both a positive effect, initiating changes that contribute to an increase in degradation resistance of materials, and a negative effect, consisting in the creation of active defect regions, near which subsequent radiation-induced defects will agglomerate.…”