Paper presents the research of austenitic steel AISI 304after ion nitriding at 400◦C and at t =4h, for the two different variants of samples distribution in the working plasma reactive chamber tube. In order to assess the effectiveness of ion nitriding variants emission spectroscopy – GDOES, surface hardness tests, microstructure research (LM) of nitrided layers were made. It has been found tha...

The article deals with mechanical properties of layers which were created by plasma nitriding technology. Nitrided layers apply to steel AISI 4140 were evaluated by metallographic method, GDOES method, microanalysis method and microhardness method. The trend of mechanical properties was experimentally obtained in dependence on length of cavity during plasma nitriding process. Moreover, the infl...

• Laser Powder Bed Fusion processed 4130 steels starting from gas and water atomized powders have been studied. Oxide-based inclusions were found within the steel matrix that activate ductile fracture during tensile testing. Micro-segregation of alloying elements was detected laser-processing both steels, which contributed to a local increase in microhardness. Water deliver comparable mechanica...

in this paper, the electrochemical behaviour of passive films formed on aisi 321 stainless steel (aisi 321)immersed in 0.1 m naoh + 0.1 m koh solution was evaluated by different electrochemical techniques. forthis purpose, passive films were formed at open circuit potential for 1 to 12 hours and then electrochemicalmeasurements were done. the polarization curves suggested that aisi 321 showed e...

Previous studies have demonstrated that the wear-corrosion synergism can be markedly affected by the loading speed. In this study, effects of the loading speed or strain rate on corrosion and corrosive wear of annealed, impact-fractured and slow bending-fractured surface layers of AISI 1045 steel in a 3.5% NaCl solution were investigated using electrochemical, scanning Kelvin probing and electr...

A generalized phase transformation kinetics model is used to understand the martensite to austenite transformation in a cold-rolled and annealed metastable AISI 301LN ultrafine-grained austenitic stainless steel. The model shows that the presence of interstitial nitrogen and heavy cold-rolling is important to promote fast transformation kinetics, through rapid nitrogen-diffusion and austenite n...