Affiliation:
1. Department of Materials Science, Faculty of Mechanical Engineering and Aeronautics , Rzeszów University of Technology , Powstanców Warszawy 12 , Rzeszów , Poland
Abstract
Abstract
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.
Reference43 articles.
1. F. CZERWINSKI: Heat treatment-conventional and novel applications. InTech, Rijeka, 2012.
2. H. CHANDLER: Heat Treater's Guide: Practices and Procedures for Irons and Steels, ASM International, Ohio 1995.
3. J.R. DAVIS: Surface hardening of steels. ASM International, Ohio 2002.
4. R. CHATTOPADHYAY: Advanced thermally assisted surface engineering processes. Kluwer Academic Publisher, Dordrecht 2004.
5. M. EGAWA, et al.: Effect of additive alloying element on plasma nitriding and carburizing behavior for austenitic stainless steels. Surf. Coat. Technol., 205(2010), 246–251, DOI: 10.1016/j.surf-coat.2010.07.093.