Metallography, Microstructure, and Analysis

, Volume 7, Issue 2, pp 203–208 | Cite as

Determination of the Root Causes for Cracking in a Large-Size Cast Ingot of AISI 4317 Steel Using Microstructural Analysis

  • Abdelhalim Loucif
  • Matthieu Bitterlin
  • Mohammad Jahazi
  • Rami Tremblay
  • Jean-Benoît Morin
  • Louis-Philippe Lapierre-Boire
Technical Article


The objective of the present work is to study the root causes for the cracking and material detachment from the external surface of a 10 metric tons high-strength low-alloy steel ingot after solidification and annealing processes. Failure analysis investigations were conducted on different samples from the cracked areas as well as from non-cracked ones. A combination of optical and electron microscopies, x-ray diffraction, and microhardness techniques were used to study and analyze the nature, morphology, and composition of the different microstructural components in the cracked regions. Thermodynamic software, Thermo-Calc® was used to corroborate and interpret the experimental findings with the existing theories. The results indicated a strong intergranular character of the cracks accompanied by the presence of second-phase particles at prior austenite grain boundaries. Segregation of chromium and manganese was demonstrated through local chemical analysis of the grain boundaries. It was concluded that a rapid cooling rate combined with the weakening of grain boundaries was at the origin of crack initiation.


Cast ingot cracking High-strength steel Grain boundaries Cooling rate Carbides Segregation 


  1. 1.
    B.G. Thomas, I.V. Samarasekera, J.K. Brimacombe, Investigation of panel crack formation in steel ingots: part II. Off-corner panel cracks. Metall. Trans. B 19B, 289–301 (1988)CrossRefGoogle Scholar
  2. 2.
    A. Kermanpur, M. Eskandari, H. Purmohamad, M.A. Soltani, R. Shateri, Influence of mould design on the solidification of heavy forging ingots of low alloy steels by numerical simulation. Mater. Des. (2010). Google Scholar
  3. 3.
    M. Bitterlin, A. Loucif, N. Charbonnier, M. Jahazi, L.-P. Lapierre-Boire, J.-B. Morin, Cracking mechanisms in large size ingots of high nickel content low alloyed steel. Eng. Fail. Anal. (2016). Google Scholar
  4. 4.
    G. Das, S. Ghosh, S.G. Chowdhury, S. Ghosh, S. Das, D.K. Bhattacharaya, Investigation of sub-surface cracks in continuous cast billets. Eng. Fail. Anal. (2003). Google Scholar
  5. 5.
    B. Santillana, R. Boom, D. Eskin, H. Mizukami, M. Hanao, M. Kawamoto, High-temperature mechanical behavior and fracture analysis of a low-carbon steel related to cracking. Metall. Mater. Trans. A (2012). Google Scholar
  6. 6.
    J. Maciejewski, C. Regulski, A case of aluminum nitride embrittlement of heavy wall cast steel. J. Fail. Anal. Prev. (2017). Google Scholar
  7. 7.
    S. Harada, S. Tanaka, H. Misumi, S. Mizoguchi, H. Horiguchi, A formation mechanism of transverse cracks on CC slab surface. ISIJ Int. 30, 310–316 (1990)CrossRefGoogle Scholar
  8. 8.
    J. Campbell, Castings: The New Metallurgy of Cast Metals, 2nd edn. (Butterworth-Heinemann, Oxford, 2003)Google Scholar
  9. 9.
    K. Tashiro, S. Watanabe, I. Kitagawa, I. Tamura, Influence of mould design on the solidification and soundness of heavy forging ingots. Trans. ISIJ 23, 312–321 (1983)CrossRefGoogle Scholar
  10. 10.
    Y. Yang, W. Luo, M. Chen, G. Shao, Simulation analysis of thermal stress during casting process of large-sized alloy steel ingot. Front. Mater. Sci. China (2009). Google Scholar
  11. 11.
    ASTM E384-16, Standard Test Method for Microindentation Hardness of Materials (ASTM International, West Conshohocken, PA, 2016)Google Scholar
  12. 12.
    G. Krauss, Solidification, segregation, and banding in carbon and alloy steels. Metall. Mater. Trans. B 34B, 781–792 (2003)CrossRefGoogle Scholar
  13. 13.
    B.L. Bramfitt, Structure/property relationships in irons and steels, in Metals Handbook Desk Edition, 2nd edn., ed. by J.R. Davis (ASM International, Materials Park, 1998), pp. 153–173Google Scholar
  14. 14.
    S. Henschel, J. Gleinig, T. Lippmann, S. Dudczig, C.G. Aneziris, H. Biermann, L. Krüger, A. Weidner, Effect of crucible material for ingot casting on detrimental non-metallic inclusions and the resulting mechanical properties of 18CrNiMo7-6 steel. Adv. Eng. Mater. (2017). Google Scholar
  15. 15.
    C.P. Sharma, Alloy Steels, Engineering Materials: Properties and Applications of Metals and Alloys (PHI Learning Pvt. Ltd, Delhi, 2003)Google Scholar
  16. 16.
    K. Abbaszadeh, H. Saghafian, S. Kheirandish, Effect of bainite morphology on mechanical properties of the mixed bainite–martensite microstructure in D6AC steel. J. Mater. Sci. Technol. 28(4), 336–342 (2012)CrossRefGoogle Scholar
  17. 17.
    F.C. Campbell, The Iron–Carbon System: Elements of Metallurgy and Engineering Alloys (ASM International, Materials Park, 2008), pp. 153–176. Google Scholar
  18. 18.
    W.F. Gale, T.C. Totemeier, Smithells Metals Reference Book, 8th edn. (Butterworth-Heinemann, Oxford, 2003)Google Scholar
  19. 19.
    C. Li, Z. Guangying, Intergranular fracture of low-alloy cast steel. Mater. Charact. 36, 65–72 (1996)CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature and ASM International 2018

Authors and Affiliations

  • Abdelhalim Loucif
    • 1
  • Matthieu Bitterlin
    • 1
  • Mohammad Jahazi
    • 1
  • Rami Tremblay
    • 2
  • Jean-Benoît Morin
    • 2
  • Louis-Philippe Lapierre-Boire
    • 2
  1. 1.Département de Génie MécaniqueÉcole de technologie supérieureMontréalCanada
  2. 2.Finkl Steel-SorelSaint-Joseph-de-SorelCanada

Personalised recommendations