Effect of Carburization Time and Carburization Temperature on Carburization of Mild Steel Using Carbon Nanotubes Obtained from a Horizontal CVD Reactor

Article Preview

Abstract:

This study investigates the effectiveness of carbon nanotubes (CNTs) in enhancing the surface hardness of mild steel through carburization. CNTs were synthesized via chemical vapor deposition at 700°C using iron nitrate and cobalt nitrate as precursors on CaCO₃ support. Acetylene was used as the carbon source and nitrogen as the inert gas. The as-synthesized CNTs were purified using a one-step nitric acid treatment. Characterization by SEM, TGA, and FTIR revealed CNT diameters of 42-52 nm and improved thermal stability after purification, with TGA showing mass losses of 78% for as-synthesized CNTs and 85% for purified CNTs. Low carbon steel (AISI 1018) samples were carburized with as-synthesized and purified CNTs at austenitic temperatures of 750°C and 800°C for period ranging from 10 to 50 minutes. The carburizing process involved heating at 10°C/minute, followed by a defined number of boost and diffusion steps. Surface hardness was evaluated using a Vickers FM 700 micro-hardness tester, and microstructure was checked with an Olympus SC50 optical microscope. Results show that the use of purified CNTs in the carburization displayed the highest surface hardness of 191.64 ± 4.16 GPa at 800°C for 50 minutes, representing a 32% increase over the untreated substrate (145.188 ± 2.66 GPa). As-synthesized CNTs yielded a hardness value of 177.88 ± 2.35 GPa under the same conditions. At 750°C, the percentage increase in hardness for as-synthesized CNTs and purified CNTs were 10.04% and 15.77%, respectively, compared to the untreated substrate. Higher carburization temperature and longer treatment time consistently increased the surface hardness. The use of purified CNTs resulted in an increase of 6.37% hardness when compared to that of the as-synthesized CNTs at 750°C. Microstructural changes in the steel samples confirmed improved surface hardness with both purified and unpurified CNTs, with purified CNTs showing superior performance. This study therefore provides a platform for the use of CNTs for enhancing surface hardness of steel for various industrial applications requiring enhanced mechanical properties and wear resistance in low carbon steels.

You might also be interested in these eBooks

Info:

Periodical:

Pages:

89-98

Citation:

Online since:

May 2025

Export:

Price:

Permissions CCC:

Permissions PLS:

Сopyright:

© 2025 Trans Tech Publications Ltd. All Rights Reserved

Share:

Citation:

* - Corresponding Author

[1] R.A. Higgins, Engineering metallurgy, Applied Physical Metallurgy, 5th., Vol. 1, 1993, p.474.

Google Scholar

[2] D.M. Jyotsna, Development of wear-resistant composite surface on mild steel by laser surface alloying with silicon and reactive melting, Mater. Lett. 62 (2008) 4257-4259.

DOI: 10.1016/j.matlet.2008.06.042

Google Scholar

[3] A.G. Nasibov, L.V. Popova, N.L. Karchevskaya, Means for increasing the toughness and strength of low-carbon steel, Met. Sci. Heat Treat. 29 (1987) 483-486.

DOI: 10.1007/bf01167729

Google Scholar

[4] G.A.G. Pedroza, C.A.C. De Souza, I.A. Carlos, L.R.P. Andrade Lima, Evaluation of the effect of deposition bath glycerol content on zinc–nickel electrodeposits on carbon steel,  Surf. Coat. Tech. 206 (2012) 2927-2932.

DOI: 10.1016/j.surfcoat.2011.12.024

Google Scholar

[5] K.P. Rao, A.V. Sreenu, H.K. Rafi, M.N. Libin, K. Balasubramaniam, Tool steel and copper coatings by friction surfacing - A thermography study, J. Mater. Process. Technol. 212 (2012) 402-407.

DOI: 10.1016/j.jmatprotec.2011.09.023

Google Scholar

[6] J. Gandra, R.M. Miranda, P. Vilaca, H. Krohn, M. Beyer, J.F. Dos Santos, Friction Surfacing - a review, J. Mater. Process. Technol.214 (2014) 1062-1093.

DOI: 10.1016/j.jmatprotec.2013.12.008

Google Scholar

[7] A. Heidarpour, M.A. Bradford, K.A.M. Othman, Thermoelastic flexural-torsional buckling of steel arches, J. Constr. Steel Res. 67 (2011) 1806-1820.

DOI: 10.1016/j.jcsr.2011.05.005

Google Scholar

[8] R.E. Ali, M.G. Milica, Z.J. Branimir, N. Branimir, N. The influence of thin benzoate-doped polyaniline coatings on corrosion protection of mild steel in different environments, Prog. Org. Coat. 76 (2013) 670-676.

DOI: 10.1016/j.porgcoat.2012.12.008

Google Scholar

[9] S.D. Colin, K.S. Christopher, J.J. Bryony, Evolution of steel surface composition with heating in vacuum and in air, Appl. Surf. Sci. 257 (2011) 10005-10017.

Google Scholar

[10] A.S. Afolabi, A.S. Abdulkareem, S.D. Mhlanga S.E. Iyuke, Synthesis and purification of bimetallic catalyzed carbon nanotubes in a horizontal CVD reactor, J. Exp. Nanosci. 6 (2011) 248-262.

DOI: 10.1080/17458080.2010.497941

Google Scholar

[11] W.A. Heer, Nanotubes and the pursuit of applications, Mater. Res. Bull. 29 (2004) 281-285.

Google Scholar

[12] B. Roman, M. Somenath, Mechanism of carbon nanotube growth by CVD, Chem. Phys. Lett. 424 (2006) 126-132.

Google Scholar

[13] R.H. Baughman, A.A. Zakhidov, W.A. De heer, Carbon nanotubes - the route towards applications, Sci. 297 (2002) 787-792.

DOI: 10.1126/science.1060928

Google Scholar

[14] E.T. Thostenson, W. Ren, T.W. Chou, Advances in science and technology of carbon nanotubes and their composites: a review, Compos. Sci. Technol. 61 (2003) 1899-1912.

DOI: 10.1016/s0266-3538(01)00094-x

Google Scholar

[15] V. Lordi, N. Yao, Molecular mechanics of binding in carbon-nanotube polymer composite, J. Mater. Res. 15 (2000) 2770-2779.

DOI: 10.1557/jmr.2000.0396

Google Scholar

[16] H.J.H. Lai, M.C.C. Lin, M.H. Yang, K. Li, Unusual morphologies of nanoparticles obtained by arc-discharge, Mater. Sci. Eng. 16 (2000) 23-26.

Google Scholar

[17] T. Nozaki, S. Yoshida, T. Karatsu, K. Okazaki, Atmospheric-pressure plasma synthesis of carbon nanotubes, J. Phys. D: Appl. Phys. 44 (2011) 17400-174015.

DOI: 10.1088/0022-3727/44/17/174007

Google Scholar

[18] K.L. Choy, Chemical vapour deposition of coatings, Prog. Mater. Sci. 48 (2003) 57-170.

Google Scholar

[19] C. Luca, S. Manuela. D.G. Silviano, C. Paola, N. Francesca, G. Eric, L. Serge, D.C. Maurizio, The synthesis and characterization of carbon nanotubes grown by chemical vapour deposition using a stainless steel, Carbon 49 (2011) 3307-3315.

DOI: 10.1016/j.carbon.2011.04.014

Google Scholar

[20] D. Vairavapandian, P. Vichchulada, M.D. Lay, Preparation and modification of carbon nanotubes. Review of advances and applications in catalysis and sensing, Anal. Chim. Acta 626 (2008) 119-129.

DOI: 10.1016/j.aca.2008.07.052

Google Scholar

[21] N. Zhao, C. He, J. Li, Z. Jiang, Y.Li, Study on purification and tip-opening of CNTs fabricated by CVD, Mater. Res. Bull. 41 (2006) 2204-2209.

DOI: 10.1016/j.materresbull.2006.04.029

Google Scholar

[22] A.S. Afolabi, A. S. Abdulkareem, S.E. Iyuke, Synthesis of carbon nanotubes and nanoballs by swirled floating catalyst chemical vapour deposition method, J. Exp. Nanosci. 2 (2007) 269-277.

DOI: 10.1080/17458080701745658

Google Scholar

[23] S.D. Mhlanga, K.C. Mondal, R. Carter, M.J. Witcomb, N.J. Coville, The effect of synthesis parameters on the catalytic synthesis of multiwalled carbon nanotubes using Fe-Co/CaCO3 catalysts, S. Afr. J. Chem. 62 (2009) 67-76.

Google Scholar

[24] I.D. Rosca, F. Watari, M. Uo, T. Akasaka, Oxidation of multiwalled carbon nanotubes by nitric acid, Carbon 43 (2005) 3124-3131.

DOI: 10.1016/j.carbon.2005.06.019

Google Scholar

[25] S.H. Su, W.T. Chiang, C.C. Lin, M. Yokoyama, Multi-wall carbon nanotubes: purification, morphology and field emission performance, Phys. E: Low-Dimens. Syst. Nanostructures 40 (2008) 2322-2326.

DOI: 10.1016/j.physe.2007.09.087

Google Scholar

[26] R. Gorochiewicz, The kinetics of low-pressure carburizing of alloy steels, Vac. 86 (2011) 448-451.

Google Scholar

[27] T. Ebbensen, A. Ajayan, H. Huira, K. Tanigaki, Purification of carbon nanotubes, Nature 367 (1940) 519.

Google Scholar

[28] E.R. Edwards, E.F. Antunes, E.C. Botleho, M.R. Baldan, E.J. Corat, Evaluation of residual iron in carbon nanotubes purified by acid treatment, Appl. Surf. Sci. 258 (2011) 641-648.

DOI: 10.1016/j.apsusc.2011.07.032

Google Scholar

[29] A.G. Osorio, I.C.L. Silveira, V.L. Bueno, C.P. Bergmann, H2SO4/HNO3/HCl-Functionalization and its effect on dispersion of carbon nanotubes in aqueous media. Appl. Surf. Sci. 255 (2008) 2485-2489.

DOI: 10.1016/j.apsusc.2008.07.144

Google Scholar

[30] S. Porro, S. Musso, M. Vinante, L. Vanzetti, M. Anderle, F. Trotta, A. Tagliaferro, Purification of carbon nanotubes grown by thermal CVD, Phys. E: Low Dimen. Syst. Nanostructures 37 (2007) 58-61.

DOI: 10.1016/j.physe.2006.07.014

Google Scholar

[31] M.A.M. Motchelaho, H. Xiong, M. Moyo, L.L. Jewel, N.J. Coville, Effect of acid treatment on the surface of multi-walled carbon nanotubes prepared from Fe-Co supported on CaCO3: Correlation with Fischer-Tropsch catalyst activity, J. Mol. Catal. A: Chem. 335 (2011) 189-198.

DOI: 10.1016/j.molcata.2010.11.033

Google Scholar

[32] C.J. Woo. H.K. Chong, Formation of austenite from a ferrite-pearlite microstructure during annealing. J. Mater. Sci. 20 (1985) 4392-4398.

DOI: 10.1007/bf00559327

Google Scholar

[33] S. Abdalla, F. Al-Marzouki, A.A. Al-Ghamdi, and A. Abdel-Daiem, Different technical applications of carbon nanotubes, Nanoscale Research Letters,10(1) (2015) 358.

DOI: 10.1186/s11671-015-1056-3

Google Scholar

[34] Y. Li, B. Wu, Y. Xiong, Q. Yuan, and H. Cui, Microstructure evolution of 20CrMnTi steel during vacuum carburizing and quenching process, Materials Research Express, 7(1) (2020) 016533.

Google Scholar

[35] T. Turpin, J. Dulcy, and M. Gantois, Carbon diffusion and phase transformations during gas carburizing of high-alloyed stainless steels: Experimental study and theoretical modeling, Metallurgical and Materials Transactions A, 47 (4) (2016) 1725-1738, 2016.

DOI: 10.1007/s11661-005-0271-4

Google Scholar

[36] S. Karabelchtchikova and R. D. Sisson Jr., Carbon diffusion in steels: A numerical simulation of vacuum carburizing," Journal of Phase Equilibria and Diffusion, 37 (6) (2016), 680-689.

Google Scholar