Journal of Failure Analysis and Prevention

, Volume 10, Issue 3, pp 245–248 | Cite as

Failure Investigation of a Diesel Engine Piston Pin

  • Xiao-lei Xu
  • Zhi-wei Yu
Technical Article---Peer-Reviewed


Transverse and longitudinal cracking took place on a diesel engine piston-pin used in a truck in service. The external circle and internal hole surfaces of piston-pin are specified to be carburized. The cracks originated from the internal hole surface and propagated, by fatigue, towards the external circle. The microstructure and microhardness profiles indicate that the serious decarburization occurred on the internal hole surface and that the hardening case was not present. The occurrence of the decarburization in the surface region of the internal hole decreases the fatigue strength to levels far below those for a carburized surface so failure initiated easily at the internal hole surface. To assure against similar failures in the future, make sure that the region around the internal hole obtains the specified depth of hardened layer.


Piston-pin Decarburization Carburizing process Fatigue fracture Failure analysis 


  1. 1.
    Determination of carburized depth and metallographic examination of carburizing structure, China Standard, GB9450 (1994)Google Scholar
  2. 2.
    Metals Handbook: Fractography and Atlas of Fractographs, vol. 9, 8th edn. American Society for Metals, Metals Park, OH (1974)Google Scholar
  3. 3.
    Fernandes, P.J.L.: Tooth bending fatigue failure in gear. Eng. Fail. Anal. (3), 219–225 (1996)Google Scholar

Copyright information

© ASM International 2010

Authors and Affiliations

  1. 1.Electromechanics and Material Engineering CollegeDalian Maritime UniversityDalianP.R. China

Personalised recommendations