Open AccessControl of kinetics of plasma assisted nitriding process of Ni-base alloys by substrate roughness
Author(s) -
W. Nowak
Publication year - 2020
Publication title -
advances in manufacturing science and technology
Language(s) - English
Resource type - Journals
eISSN - 2300-2565
pISSN - 1895-9881
DOI - 10.2478/amst-2019-0019
Subject(s) - nitriding , materials science , kinetics , metallurgy , surface roughness , polishing , surface finish , alloy , grinding , composite material , layer (electronics) , physics , quantum mechanics
The present study investigated the effect of surface roughness on plasma assisted nitriding (PAN) process kinetics of Ni-base alloys. Two model alloys, namely Ni-10Cr and Ni-14Cr-4Al (wt.%) and commercial Rene 80, were examined. To elucidate the effect of surface roughness on nitriding kinetics, three methods of surface preparation were used, (1) polishing up with 1 μm diamond suspension, (2) grinding up to 220 grit sand-paper, and (3)grit blasting. The samples from each type of material were nitrided under the same conditions and investigated after processing. It was found that increase in roughness results in decreasing nitriding kinetics. The decrease of nitriding kinetics depends on alloy chemical composition, namely more complex chemistry resulted in smaller decrease of kinetics. Moreover, grit-blasting was found to be an improper method for surface preparation for PAN. The responsible mechanism for the effect of surface roughness on PAN kinetics of Ni-base alloys was proposed.