| Peer-Reviewed

Failure Analysis Report on Fractured Torsion Bar in Suspension of a Vehicle

Received: 29 March 2022    Accepted: 20 April 2022    Published: 28 April 2022
Views:       Downloads:
Abstract

Accidents caused by fractured torsion bars in off-road vehicles (ORVs) have occurred during road tests. Through visual inspection of the fracture in the failed samples, the preliminary conclusion is that the typical torsional fracture occurs according to its ratchet shape and 45-degree cracking direction to the bar axis. The crack initiated at the side surface of the fillet on the spline end. All failed parts during road tests have identical fracture modes and crack initiation sites, which implies that they have identical failure reasons. Techniques such as scanning electron microscopy (SEM), metallographic observation, hardness test and spectral component analysis have been performed to obtain detailed information to diagnose the cause of failure. The result reveals that the fracture was caused by fatigue cracking initiated from the spline fillet. In addition, SEM images of the intergranular feature of the fracture initiation zone demonstrate that the untimely formation of a fatigue core and very quick expansion of the crack directly result from over-brittleness. This behavior can be ascribed to insufficient tempering after the quenching process, which was confirmed by a tempering simulation experiment: after the tempering experiment, the artificial struck fracture of the sample became a 100% dimple fracture, and the hardness distribution became more uniform and reasonable. Thus, the brittleness was eliminated, and the strength was ensured after an expanding tempering time. This investigation can provide reference value for solving and preventing such types of failures.

Published in International Journal of Materials Science and Applications (Volume 11, Issue 2)
DOI 10.11648/j.ijmsa.20221102.13
Page(s) 55-61
Creative Commons

This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited.

Copyright

Copyright © The Author(s), 2024. Published by Science Publishing Group

Keywords

Torsion Bar, Spline, Fatigue, Over-brittleness, Tempering

References
[1] J. Yamakawa, K. Watanabe, A spatial motion analysis model of tracked vehicles with torsion bar type suspension. Journal of Terramechanics, 2004. 41 (2-3): pp. 113-126.
[2] G. P. S. Gagneza, S. Chandramohan, Estimation of Road Loads and Vibration Transmissibility of Torsion Bar Suspension System in a Tracked Vehicle. Journal of the Institution of Engineers (India), 2019, Ser. C. 100: pp. 747-761.
[3] S. A. Rodríguez, F. A. Quiceno, J. J. Coronado, Investigation of the failure of an automobile torsion bar. Journal of Failure Analysis and Prevention, 2009, 10 (1): pp. 11-17.
[4] V. Mocilnik, N. Gubeljak, J. Predan, Influence of presetting on fatigue lifetime of torsion bars. Procedia Engineering, 2011, 10: pp. 213-218.
[5] Zhiwei Yu, Xiaolei Xu, Zhi Yang, Yuanyuan Li, Case internal oxidation and intergranular fracture of carburized splined-shaft. Engineering Failure Analysis, 2012, 22: pp. 141-151.
[6] Xiaolei Xu, Zhiwei Yu, Failure analysis of a truck diesel engine crankshaft. Engineering Failure Analysis, 2018, 92: pp. 84-94.
[7] S. Zangeneh, M. Ketabchi, A. Kalaki, Fracture failure analysis of AISI 304L stainless steel shaft. Engineering Failure Analysis, 2014, 36: pp. 155-165.
[8] P. Peralta, C. Laird, Chap. 18-Fatigue of Metals, Physical Metallurgy, 5th ed., D. E. Laughlin, K. Hono, Ed., Elsevier, 2015, pp. 1765-1880.
[9] Taylor, D., CHAPTER 9 - Fatigue: Predicting Fatigue Limit and Fatigue Life, in the Theory of Critical Distances, 2007, Elsevier Science Ltd: Oxford. pp. 163-196.
[10] Taylor, D. CHAPTER 11 - Multiaxial Loading: Fracture and Fatigue Under Complex Stress States, The Theory of Critical Distances, 2007, Elsevier Science Ltd: Oxford. pp. 213-233.
[11] T. Sekercioglu, Failure analysis of torsion bar of projectile weaving machine. Journal of Failure Analysis and Prevention, 2010, 10 (5): pp. 363-366.
[12] Zhi Sun. Chap. 5-Failure Analysis of Fatigue Fracture, Failure Analysis: Fundamentals and Applications, 1st ed, 2005, China Machine Express: pp. 142-162 (in Chinese).
[13] Renzhi Wang, Peiyuan Wu. CMES, Chap. 4- Judgment of Fatigue Failure, Fatigue Failure Analysis, 1st ed, 1987, China Machine Express, pp 109-166 (in Chinese).
[14] Li Li, Youli Zhu, Yuanlin Huang, Fracture Failure Analysis of Torsion Bar with Surface Defects. China Surface Engineering, 2005, 01: pp. 47-49.
[15] I. Barsoum, F. Khan, Z. Barsoum, Analysis of the torsional strength of hardened splined shafts. Materials & Design, 2014, 54: pp. 130-136.
[16] Xueyuan Gong, Hongjun Dong, Fracture failure analysis of torsion bar spring. MW Metal Forming, 2022, 03: pp. 72-74.
[17] Xin Haohui, Correia José A. F. O., Veljkovic Milan et al. Residual stress effects on fatigue life prediction using hardness measurements for butt-welded joints made of high strength steels. International Journal of Fatigue, 2021, 147: 106175.
[18] D. McClaflin, A. Fatemi, Torsional deformation and fatigue of hardened steel including mean stress and stress gradient effects. International Journal of Fatigue, 2003, 26 (7): pp. 773-784.
[19] V. T. Troshchenko, Nonlocalized Fatigue Damage to Metals and Alloys. Materials Science, 2006, 42 (1): pp. 20-33.
[20] Xianwen Wang, Shuaijun Dong, Chaolei Zhang, Bo Jiang, Analysis of torsion bar failure occurring during the pre-strained manufacturing for heavy off-road tracked vehicles. Engineering Failure Analysis, 2022, 133: 105956.
Cite This Article
  • APA Style

    Nan Nan, Jijun Feng. (2022). Failure Analysis Report on Fractured Torsion Bar in Suspension of a Vehicle. International Journal of Materials Science and Applications, 11(2), 55-61. https://doi.org/10.11648/j.ijmsa.20221102.13

    Copy | Download

    ACS Style

    Nan Nan; Jijun Feng. Failure Analysis Report on Fractured Torsion Bar in Suspension of a Vehicle. Int. J. Mater. Sci. Appl. 2022, 11(2), 55-61. doi: 10.11648/j.ijmsa.20221102.13

    Copy | Download

    AMA Style

    Nan Nan, Jijun Feng. Failure Analysis Report on Fractured Torsion Bar in Suspension of a Vehicle. Int J Mater Sci Appl. 2022;11(2):55-61. doi: 10.11648/j.ijmsa.20221102.13

    Copy | Download

  • @article{10.11648/j.ijmsa.20221102.13,
      author = {Nan Nan and Jijun Feng},
      title = {Failure Analysis Report on Fractured Torsion Bar in Suspension of a Vehicle},
      journal = {International Journal of Materials Science and Applications},
      volume = {11},
      number = {2},
      pages = {55-61},
      doi = {10.11648/j.ijmsa.20221102.13},
      url = {https://doi.org/10.11648/j.ijmsa.20221102.13},
      eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ijmsa.20221102.13},
      abstract = {Accidents caused by fractured torsion bars in off-road vehicles (ORVs) have occurred during road tests. Through visual inspection of the fracture in the failed samples, the preliminary conclusion is that the typical torsional fracture occurs according to its ratchet shape and 45-degree cracking direction to the bar axis. The crack initiated at the side surface of the fillet on the spline end. All failed parts during road tests have identical fracture modes and crack initiation sites, which implies that they have identical failure reasons. Techniques such as scanning electron microscopy (SEM), metallographic observation, hardness test and spectral component analysis have been performed to obtain detailed information to diagnose the cause of failure. The result reveals that the fracture was caused by fatigue cracking initiated from the spline fillet. In addition, SEM images of the intergranular feature of the fracture initiation zone demonstrate that the untimely formation of a fatigue core and very quick expansion of the crack directly result from over-brittleness. This behavior can be ascribed to insufficient tempering after the quenching process, which was confirmed by a tempering simulation experiment: after the tempering experiment, the artificial struck fracture of the sample became a 100% dimple fracture, and the hardness distribution became more uniform and reasonable. Thus, the brittleness was eliminated, and the strength was ensured after an expanding tempering time. This investigation can provide reference value for solving and preventing such types of failures.},
     year = {2022}
    }
    

    Copy | Download

  • TY  - JOUR
    T1  - Failure Analysis Report on Fractured Torsion Bar in Suspension of a Vehicle
    AU  - Nan Nan
    AU  - Jijun Feng
    Y1  - 2022/04/28
    PY  - 2022
    N1  - https://doi.org/10.11648/j.ijmsa.20221102.13
    DO  - 10.11648/j.ijmsa.20221102.13
    T2  - International Journal of Materials Science and Applications
    JF  - International Journal of Materials Science and Applications
    JO  - International Journal of Materials Science and Applications
    SP  - 55
    EP  - 61
    PB  - Science Publishing Group
    SN  - 2327-2643
    UR  - https://doi.org/10.11648/j.ijmsa.20221102.13
    AB  - Accidents caused by fractured torsion bars in off-road vehicles (ORVs) have occurred during road tests. Through visual inspection of the fracture in the failed samples, the preliminary conclusion is that the typical torsional fracture occurs according to its ratchet shape and 45-degree cracking direction to the bar axis. The crack initiated at the side surface of the fillet on the spline end. All failed parts during road tests have identical fracture modes and crack initiation sites, which implies that they have identical failure reasons. Techniques such as scanning electron microscopy (SEM), metallographic observation, hardness test and spectral component analysis have been performed to obtain detailed information to diagnose the cause of failure. The result reveals that the fracture was caused by fatigue cracking initiated from the spline fillet. In addition, SEM images of the intergranular feature of the fracture initiation zone demonstrate that the untimely formation of a fatigue core and very quick expansion of the crack directly result from over-brittleness. This behavior can be ascribed to insufficient tempering after the quenching process, which was confirmed by a tempering simulation experiment: after the tempering experiment, the artificial struck fracture of the sample became a 100% dimple fracture, and the hardness distribution became more uniform and reasonable. Thus, the brittleness was eliminated, and the strength was ensured after an expanding tempering time. This investigation can provide reference value for solving and preventing such types of failures.
    VL  - 11
    IS  - 2
    ER  - 

    Copy | Download

Author Information
  • School of Science, Hubei University of Automotive Technology, Shiyan, China

  • Technical Center of Dongfeng Commercial Vehicle, Dongfeng Motor Corporation, Wuhan, China

  • Sections