Journal of Failure Analysis and Prevention

, Volume 11, Issue 6, pp 679–683 | Cite as

Investigation of Failure in Automotive Exhausts

  • M. Abdoli
  • H. Rahimi
  • A. Godarzizadeh
Technical Article---Peer-Reviewed


Initial investigation of some automotive exhausts that failed during operation in this study revealed that most of the fractures occurred at the position where the diameter of the exhausts changed. Light optical microscopy (OM) and scanning electron microscopy (SEM) examinations have shown that the aluminized coating in the failure area had become cracked during the manufacturing process. This situation led to substrate oxidation and cracking at the elevated temperatures and under cyclic load conditions. It is found that the failure is ultimately due to fatigue caused by the combination of mechanical vibrations and thermal cycles. In addition, oxidation of the crack tip may have accelerated the fatigue crack growth process. A design change mitigated the tendency for failure.


Exhaust failure Automotive exhaust Fatigue Aluminized coating 


  1. 1.
    Hoffmann, C., Gümpel, P.: Pitting corrosion in the wet section of the automotive exhaust systems. J. Achiev. Mater. Manuf. Eng. 34(2), 115–121 (2009)Google Scholar
  2. 2.
    Chen, C., Li, D.Y., Shang, C.J.: Nanocrystallization of aluminized surface of carbon steel for enhanced resistances to corrosion and corrosive wear. Electrochim. Acta 55, 118–124 (2009)CrossRefGoogle Scholar
  3. 3.
    Chang, S., Jun, J.H.: Corrosion resistance of automotive exhaust materials. J. Mater. Sci. Lett. 18, 419–421 (1999)CrossRefGoogle Scholar
  4. 4.
    Chen, C., Shang, C.J., Li, D.Y.: Surface nanocrystallization of Al-plated steel for application in the exhaust system of vehicles. Wear 267, 345–349 (2009)CrossRefGoogle Scholar
  5. 5.
    ASM Metals Handbook, vol. 5: Surface Engineering, p. 619. ASM International, Materials Park, OH (1994)Google Scholar

Copyright information

© ASM International 2011

Authors and Affiliations

  1. 1.Department of EngineeringTarbiat Modares UniversityTehranIran
  2. 2.Research & Development SectionFaragaman Misagh Co.KarajIran
  3. 3.Research & Development SectionSazehgostar Saipa Co.TehranIran

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