Abstract
Hydraulic amplifier valve (HAV) spools are made up of AISI 440C stainless steel and are used as flow control devices of actuators. Failure of three numbers of HAV spools observed near the undercut region is investigated in this paper. Microstructural analysis of the failed spools revealed the presence of large amount of primary and secondary carbides in the matrix of tempered martensite. Fractographic analysis of failed HAV spools revealed features typical of overload fracture. Corrosion pits of 300–350 µm depth are observed around the periphery of the fracture surface at a few locations of the failed HAV spools. Failure of the spools is found under the application of mechanical loads, where load-bearing capability of the spools is reduced due to stress concentration near the undercut region owing to the presence of corrosion pits. This was further assisted by large primary carbides present abundantly in this alloy.
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References
N.M. Tri, D.N.C. Nam, H.G. Park, K.K. Ahn, Trajectory control of an electro hydraulic actuator using an iterative backstep** control scheme. Mechatronics. 29, 96–102 (2015). https://doi.org/10.1016/J.MECHATRONICS.2014.10.002
J. Nilsson, Position Control of an Electro-Hydraulic Servo-Valve Identification, modelling, Control and Implementation, (2016).
K.-E. Rydberg, Hydraulic servo systems: dynamic properties and control, 2016.
Y.M. Sam, K. Hudha, in Modelling and force tracking control of hydraulic actuator for an active suspension system, 2006 1st IEEE Conf. Ind. Electron. Appl. (2006). https://doi.org/10.1109/ICIEA.2006.257242.
S.K. Manwatkar, A. Bahrudheen, S.B. Tiwari, S.V.S. Narayana Murty, P. Ramesh Narayanan, Failure analysis of AISI 440C steel ball screws used in the actuator system of a satellite launch vehicle. J. Fail. Anal. Prev. 17, 505–512 (2017). https://doi.org/10.1007/s11668-017-0268-5
T.Y.C.W.J. Yang, Martensitic transformations in AISI 440C stainless steel. Mater. Sci. Eng. A. 438, 276–280 (2006)
K. Jalaja, S.K. Manwatkar, P. Anand, R. Rejith, S.V.S. Narayana Murty, Metallurgical analysis of surface distress on balls during the operation of AISI 440C ball bearings for satellite applications. Eng. Fail. Anal. 124, 105376 (2021). https://doi.org/10.1016/j.engfailanal.2021.105376
H.K.D.H. Bhadeshia, Steels for bearings. Prog. Mater. Sci. 57, 268–435 (2012). https://doi.org/10.1016/j.pmatsci.2011.06.002
J.R.J. Marcuci, E.C. De Souza, C.C. Camilo, P.L. Di Lorenzo, J.M.D.A. de Rollo, Corrosion and microstructural characterization of martensitic stainless steels submitted to industrial thermal processes for use in surgical tools. Rev. Bras. Eng. Biomed. 30, 257–264 (2014). https://doi.org/10.1590/rbeb.2014.025
P.D. Pierre, R. Roberge, Handbook of Corrosion Engineering, Second Edition, mcgraw-Hill Education, 2012. https://www.accessengineeringlibrary.com/content/book/9780071750370 26 Dec 2022
P. Guo, E.C. La Plante, B. Wang, X. Chen, M. Balonis, M. Bauchy, G. Sant, Direct observation of pitting corrosion evolutions on carbon steel surfaces at the nano-to-micro- scales. Sci. Rep. 2018 81. 8, 1–12 (2018). https://doi.org/10.1038/s41598-018-26340-5
Acknowledgments
The Group Director, Materials and Metallurgy Group and the Deputy Director, Materials and Mechanical Entity are acknowledged by the authors for their support and encouragement during the completion of this study. The authors also give Dr. A Venugopal, MCTG credit for providing an optical profilometer to determine the depth of a pit.
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Jalaja, K., Manwatkar, S.K., Gupta, R.K. et al. Metallurgical Analysis of Failed AISI 440C Hydraulic Amplifier Valve Spool for Launch Vehicle Actuators. J Fail. Anal. and Preven. 23, 728–738 (2023). https://doi.org/10.1007/s11668-023-01597-9
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DOI: https://doi.org/10.1007/s11668-023-01597-9