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Improving Surface Hardness of EN31 Steel by Surface Hardening and Cryogenic Treatment

  • M. K. Chaanthini
  • Arul SanjiviEmail author
Original Contribution
  • 35 Downloads

Abstract

Steels are subjected to different conventional heat treatment (CHT) processes such as annealing, normalizing, hardening, tempering, quenching, and stress relieving, to improve the mechanical properties and surface coating methods such as electroplating, laser coating, CVD, and PVD, and to enhance the tribological and corrosion properties. Cryogenic treatment is usually performed after CHT to further improve these properties. Components with friction surfaces require high surface hardness in order to resist wear. In this work, EN31 steel used in bearings, spline shafts, and tiller blades, is surface-hardened using gas tungsten arc (GTA). To further improve the hardness, cryogenic treatment was done. GTA torch uses thoriated tungsten (2%) electrode to apply the heat on the friction surface. The welding current and angle of the electrode tip were varied to obtain different heat inputs during surface hardening process. Cryogenic treatment was done for five different soaking periods at − 50 °C [shallow cryogenic treatment (SCT)] and − 196 °C [deep cryogenic treatment (DCT)]. Shallow cryogenic treatment was performed using dry ice, and deep cryogenic treatment was performed using liquid nitrogen. Micro-hardness and microstructures of the specimen were studied. Microstructure study shows that considerable amount of retained austenite has been transformed to plate martensite with precipitates of carbide particles, increasing the hardness of the surface. Surface hardness increases with current and soaking period. The maximum hardness is obtained at 200 A for all electrode tip angles. The maximum hardness is obtained at 15 h of soaking period. Specimens treated at − 190 °C were found to exhibit higher hardness than specimens treated at − 50 °C. Further, 200 A welding current with 45° electrode tip angle and 15 h of soaking period for both SCT and DCT is found to produce maximum hardness.

Keywords

EN 31 Surface hardening GTA heat source Cryogenic treatment Hardness Martensite 

Notes

References

  1. 1.
    X. Tao, C. Li, L. Han, J. Gu, J. Mater. Res. Technol. 5, 1–13 (2015)Google Scholar
  2. 2.
    K.T. Cho, K. Song, S.H. Oh, Y.K. Lee, W.B. Lee, Surf. Coat. Technol. 232, 912–919 (2013)CrossRefGoogle Scholar
  3. 3.
    M. Ramezani, T. Pasang, Z. Chen, T. Neitzert, D. Au, J. Mater. Res. Technol. 4, 114–125 (2015)CrossRefGoogle Scholar
  4. 4.
    R. Fragoudakis, S. Karditsas, G. Savaidis, N. Michailidis, Procedia Eng. 74, 309–312 (2014)CrossRefGoogle Scholar
  5. 5.
    S. Sackl, G. Kellezi, H. Leitner, H. Clemens, S. Primig, Mater. Today Proc. 2, S635–S638 (2015)CrossRefGoogle Scholar
  6. 6.
    J. Suchanek, V. Kuklik, Wear 267, 2100–2108 (2009)CrossRefGoogle Scholar
  7. 7.
    S. Hernandez, J. Hardell, H. Winkelmann, M.R. Ripoll, B. Prakash, Wear 338–339, 27–35 (2015)CrossRefGoogle Scholar
  8. 8.
    S. Zhirafar, A. Rezaeian, M. Pugh, J. Mater. Process. Technol. 186, 298–303 (2007)CrossRefGoogle Scholar
  9. 9.
    D. Senthilkumar, I. Rajendran, M. Pellizzari, J. Siiriainen, J. Mater. Process. Technol. 211, 396–401 (2011)CrossRefGoogle Scholar
  10. 10.
    M. Preciado, P.M. Bravo, J.M. Alegre, J. Mater. Process. Technol. 176, 41–44 (2006)CrossRefGoogle Scholar
  11. 11.
    M. Singh, H. Singh, Int. J. Res. Eng. Technol. 03, 169–173 (2014)Google Scholar
  12. 12.
    A. Molinari, M. Pellizzari, S. Gialanella, G. Straffelini, K.H. Stiasny, J. Mater. Process. Technol. 118, 350–355 (2001)CrossRefGoogle Scholar
  13. 13.
    M. Pérez, C. Rodríguez, F.J. Belzunce, Procedia Mater. Sci. 3, 604–609 (2014)CrossRefGoogle Scholar
  14. 14.
    S.S. Gill, H. Singh, R. Singh, J. Singh, Int. J. Adv. Manuf. Technol. 48, 175–192 (2010)CrossRefGoogle Scholar
  15. 15.
    T. Yugandhar, P.K. Krishnan, C.V.B. Rao, R. Kalidas, 6th Int. Tool. Conf. 24, 671–684 (2002)Google Scholar
  16. 16.
    A. Oppenkowski, S. Weber, W. Theisen, J. Mater. Process. Technol. 210, 1949–1955 (2010)CrossRefGoogle Scholar
  17. 17.
    P.I. Patil, R.G. Tated, Int. J. Comput. Appl. 9, 10–29 (2012) Google Scholar
  18. 18.
    D. Das, A.K. Dutta, K.K. Ray, Wear 267, 1371–1380 (2009)CrossRefGoogle Scholar
  19. 19.
    P. Sekhar Babu, Int. J. Res. Eng. Technol. 3, 17–20 (2015)Google Scholar
  20. 20.
    A. Idayan, A. Gnanavelbabu, K. Rajkumar, Procedia Eng. 97, 1683–1691 (2014)CrossRefGoogle Scholar
  21. 21.
    K. Kamei, A.G. William, L. Koveile, N. Ahmad, A. Chakravorty, R. Davis, IOSRJ. Mech. Civ. Eng. 11, 17–22 (2014)CrossRefGoogle Scholar
  22. 22.
    S. Harish, A. Bensely, D. Mohan Lal, A. Rajadurai, G.B. Lenkey, J. Mater. Process. Technol. 209, 3351–3357 (2009)CrossRefGoogle Scholar
  23. 23.
    R. Saravanan, R. Sellamuthu, Appl. Mech. Mater. 592–594, 53–57 (2014)CrossRefGoogle Scholar
  24. 24.
    R. Saravanan, R. Sellamuthu, Procedia Eng. 97, 1348–1354 (2014)CrossRefGoogle Scholar
  25. 25.
    A.U. Orlowicz, A. Trytek, Weld. Int. 19, 341–348 (2005)CrossRefGoogle Scholar
  26. 26.
    S.G. Sapate, A.D. Chopde, P.M. Nimbalkar, D.K. Chandrakar, Mater. Des. 29, 613–621 (2008)CrossRefGoogle Scholar
  27. 27.
    G. Kocher, O. Parkash, S. Vardhan, Int. J. Emerg. Technol. Adv. Eng. 2, 102–105 (2012)Google Scholar
  28. 28.
    A.A. Sadek, M. Ushio, F. Matsuda, Metall. Trans. A Phys. Metall. Mater. Sci. 21, 3221–3236 (1990)CrossRefGoogle Scholar
  29. 29.
    M. Ushio, A.A. Sadek, F. Matsuda, Plasma Chem. Plasma Process. 11, 81–101 (1991)CrossRefGoogle Scholar
  30. 30.
    S. Murugappan, S. Arul, C. Campus, Int. J. Appl. Eng. Res. 10, 21549–21563 (2015)Google Scholar
  31. 31.
    S. Murugappan, S. Arul, Int. J. Appl. Eng. Res. 10, 31329–31340 (2015)Google Scholar
  32. 32.
    S. Murugappan, S. Arul, S.K. Narayanan, Procedia CIRP 35, 61–66 (2015)CrossRefGoogle Scholar
  33. 33.
    A.W. Orłowicz, A. Trytek, Metall. Mater. Trans. A 34, 2973–2984 (2003)CrossRefGoogle Scholar
  34. 34.
    N.A. Özbek, A. Çiçek, M. Gülesin, O. Özbek, Int. J. Mach. Tools Manuf. 86, 34–43 (2014)CrossRefGoogle Scholar
  35. 35.
    R. Choudhary, H. Kumar, R.K. Garg, Indian J. Eng. Mater. Sci. 17, 91–98 (2010)Google Scholar
  36. 36.
    N.H. Jun, Y. Lv, L. Mi, H. Liu, Int. Conf. Mater. Mech. Manuf. Eng. (2015).  https://doi.org/10.2991/ic3me-15.2015.210 Google Scholar
  37. 37.
    B.R. Chandra, S. Arul, R. Sellamuthu, Procedia Mater. Sci. 5, 2369–2375 (2014)CrossRefGoogle Scholar
  38. 38.
    F.W. Breyfogle, Implementing Six Sigma—Smarter Solutions Using Statistical Methods (Wiley, Hoboken, 1999)Google Scholar

Copyright information

© The Institution of Engineers (India) 2019

Authors and Affiliations

  1. 1.Department of Mechanical Engineering, Amrita School of EngineeringAmrita Vishwa VidyapeethamCoimbatoreIndia

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