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Journal of Failure Analysis and Prevention

, Volume 14, Issue 4, pp 504–508 | Cite as

Investigation into the Cracking of SAILMA 350 HI During Forming

  • Biswajit Sarkar
  • Nalini Kant Roy
Technical Article---Peer-Reviewed
  • 80 Downloads

Abstract

Vanadium microalloyed hot rolled steel of 13.8 mm thickness, when hot formed at 900 °C into axle housings were rejected because of a prominent crack running along the length of the component. A detailed metallurgical investigation revealed that the cracking during forming was the result of the opening up of pre-existing fine crack along the length of the hot rolled coils. These cracks were barely visible on the hot rolled coils that were formed into the axle housings. Metallographic and hardness tests indicated that these cracks might have been generated as a result of decarburization of the slab during soaking that led to a softer surface layer of the slab. During subsequent hot rolling mechanical defect might have been caused on the decarburized surface that is much softer than a material with a usual carbon content. It was concluded that soaking in the reheating furnace with low carbon potential might have led to extensive decarburization of the slabs. Soaking in a furnace atmosphere with adequate carbon potential was recommended as a remedial measure to prevent decarburization of the surface layers of the slabs.

Keywords

Decarburization Crack Forming 

Notes

Acknowledgments

The authors thankfully acknowledge the patronage of the management of R & D Centre for Iron and Steel and Bokaro Steel Limited for execution of the present investigation. Also, the support received from the laboratory staff for carrying out the various tests is being gratefully acknowledged. Thanks are due to Dr. G. Sahoo for his help in taking the photographs.

References

  1. 1.
    G. Krauss, Physical Metallurgy and Heat Treatment of Steel, in Metals Handbook, Desk edn., ed. by H.E. Boyer, T.L. Gall (American Society for Metals, Metals Park, 1985), pp. 28-2–28-10Google Scholar
  2. 2.
    P.G. Shewmon, Diffusion in Solids (McGraw-Hill Book Company, New York, 1963), p. 38Google Scholar

Copyright information

© ASM International 2014

Authors and Affiliations

  1. 1.Product Development, RDCISSAILRanchiIndia
  2. 2.Department of ChemistryRanchi CollegeRanchiIndia

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