Cast iron plasma nitriding in N2 /H2 /Ar working gas: the role of auxiliary gases (H2 /Ar) in the growing kinetics of compound layers
Luís César Fontana, David Pascoal Sudaia, Abel André Cândido Recco, André Olah Neto, Paulo César Borges, Wilson Luiz Guesser
Resumo
Present paper sets out to investigate the role of N2 /H2 /Ar working gas in plasma nitriding of nodular cast iron. The proportion of N2 /H2 /Ar proved to be a relevant parameter in the growing kinetics control of the γ’-Fe4 N e ε-Fe3 N compound layers. X-ray diffraction and optical microscopy were used in order to characterize the compound layers. Results indicate that there are no generation of compound layers if the treatment is performed through plasma of pure N2 . However, even small percentages (~10%) of auxiliary gases (H2 /Ar), added to the working gas, are enough to generate compound layers as thick as 10µm (at 500 °C, and 3,0 h). In addition, it is possible to obtain γ’-Fe4 N monophasic compound layer when the nitriding process is carried out in low proportion of nitrogen in the N2 /H2 /Ar working gas mixture.
Palavras-chave
References
1 Bogaerts A, Neyts E, Gijbels R, Mullen J. Gas discharge plasmas and their applications. Spectrochimica Acta. Part B, Atomic Spectroscopy. 2002;57:609-658.
2 Edenhofer B, Grafen W, Muller Ziller JM. Plasma-carburising - a surface heat treatment process for the new century. Surface and Coatings Technology. 2001;142-144:225-234.
3 Efremenko VG, Chabak YG, Lekatou A, Karantzalis AE, Shimizu K, Fedun VI, et al. Pulsed plasma deposition of Fe-C-Cr-W coating on high-Cr-cast iron: effect of layered morphology and heat treatment on the microstructure and hardness. Surface and Coatings Technology. 2016;304:293-305.
4 Srikanth S, Saravanan P, Joseph A, Ravi K. Surface modification of commercial low-carbon steel using glow discharge nitrogen plasma and its characterization. Journal of Materials Engineering and Performance. 2013;22(9):2610-2622.
5 Binder C, Bendo T, Hammes G, Klein AN, de Mello JDB. Effect of nature of nitride phases on sliding wear of plasma nitrided sintered iron. Wear. 2015;332-333:995-1005.
6 Dong Y, Bell T, Xiaoying L, Dong H. A novel double-stage pulsed plasma bright nitriding of spheroidal graphite (SG) cast iron. Vacuum. 2018;153:217-220. http://dx.doi.org/10.1016/j.vacuum.2018.04.016.
7 Writzl V, Rovani AC, Pintaude G, Lima MSF, Guesser WL, Borges PC. Scratch resistances of compacted graphite iron with plasma nitriding, laser hardening, and duplex surface treatments. Tribology International. 2020;143:106081. http://dx.doi.org/10.1016/j.triboint.2019.106081.
8 Santos D Fo, Tschiptschin AP, Goldenstein H. Effects of shallow plasma nitriding on the surface topography of gray cast iron specimens. Surface and Coatings Technology. 2020;404:126464. http://dx.doi.org/10.1016/j.surfcoat.2020.126464.
9 Wollmann D, Soares GPPP, Grabarski MI, Weigert NB, Escobar JA, Pintaude G, et al. Rolling contact fatigue failure mechanisms of plasma-nitrided ductile cast iron. Journal of Materials Engineering and Performance. 2017;26:2017-2859. http://dx.doi.org/10.1007/s11665-017-2717-4.
10 Scholtz JS, Fontana LC, Mezaroba M. Asymmetric bipolar plasma power supply to increase the secondary electrons emission in capacitive coupling plasmas. IEEE Transactions on Plasma Science. 2018;46(8):2999-3007. http://dx.doi.org/10.1109/tps.2018.2851071.
11 Scholtz JS, Ludero A, Mezaroba M, Torres RD, Fontana LC. Working gas pressure as a control parameter of crystalline phases during pulsed plasma nitriding process. Tecnologica em Metalurgia, Materiais e Mineração. 2018;15(2):110-114. http://dx.doi.org/10.4322/2176-1523.1192.
12 Tier MAD, Kieckow F, Strohaecker TR, Rocha AS, Santos JF, Bell T. Estudo do perfil de carbono na camada nitretada do aço Aisi M2. Tecnologia em Metalurgia e Materiais. 2007;4(2):6-11. http://dx.doi.org/10.4322/tmm.00402002.
13 Egert P, Maliska AM, Silva HRT, Speller CV. Decarburation during plasma nitriding. Surface and Coatings Technology. 1999;122(1):33-38.
14 Priest JM, Baldwin MJ, Fewell MP. The action of hydrogen in low-pressure r.f.-plasma nitriding. Surface and Coatings Technology. 2001;145(1-3):152-163.
15 Hirohata Y, Tsuchiya N, Hino T. Effect of mixing of hydrogen into nitrogen plasma. Applied Surface Science. 2001;169-170:612-616.
16 Karakan M, Alsaran A, Celik A. Effects of various gas mixtures on plasma nitriding behavior of AISI 5140 steel. Materials Characterization. 2002;49:241-246.
17 Pye D. Practical nitriding and ferritic nitrocarburizing. Ohio: ASM International; 2003.
18 Fancey KS, Leyland A, Egerton D, Torres D, Matthews A. The influence of process gas characterization on the properties of plasma nitriding steel. Surface and Coatings Technology. 1995;76-77:694-699.
19 Chapman B. Glow discharge processes: sputtering and plasma etching. Hoboken: Wiley-Interscience; 1980.
20 Saloum S, Naddaf M, Alkhaled B. Diagnostics of N2–Ar plasma mixture excited in a 13.56MHz hollow cathode discharge system: application to remote plasma treatment of polyamide surface. Journal of Physics D: Applied Physics. 2008;41:045205
21 Calister WD Jr. Materials Science and Enginering:na introduction. Hoboken: Jonh Wiley & Sons; 1997.
22 Koga M, Iwata S, Muta H, Yonesu A, Kawai Y. Measurement of ion temperature in N2/Ar and O2/Ar ECR plasma. Vacuum. 2004;74:491-495.
23 Alves C Jr. Nitretação em plasma – Fundamentos e aplicações. Natal: EDUFRN; 2001.
24 Karakan M, Alsaran A, Celik A. Effects of various gas mixtures on plasma nitriding behavior of AISI 5140 steel. Materials Characterization. 2003;49:241-246.
Submitted date:
09/28/2021
Accepted date:
05/30/2022
Facebook
Google+
Twitter
LinkedIn
Mendeley
StumbleUpon
CiteULike
Reddit
Email