Journal of Failure Analysis and Prevention

, Volume 9, Issue 1, pp 74–80 | Cite as

Proposal of a New G-BOP Test to Evaluate Cracks in Weld Beads in Thin Sheets

  • José Hilton Ferreira da Silva
  • Hipolito Carvajal Fals
  • Roseana da Exaltação Trevisan
Technical Article---Peer-Reviewed


The objective of the present work is the evaluation of a proposal for a gapped bead-on-plate (G-BOP) test, used for study of hydrogen cracks in relatively thin sheets of welded steel. That new proposal consists of the replacement of the usual solid blocks by an assembly of blocks in such a way that the test can evaluate weld beads on thin sheets. Student t distribution is applied to examine the functionality of the proposed test. Weld metals were deposited with flux-cored wires E71T-1 and E71T8-K6, with diameters of 1.6 and 1.7 mm, respectively, under two different preheating temperatures. Metal susceptibility to hydrogen cracking was evaluated by the presence and percentage of cracks in the weld metal. In order to evaluate and verify the functionality of the new G-BOP test proposal, the following were examined: efficiency of the new test in inducing hydrogen cracks in the weld metal, result replicability, fracture modes present in cracks, and the cooling rate imposed on the welding zone. Results showed that the new G-BOP test proposal is viable; results were replicable and the test was efficient in inducing cracks in weld metal with a confidence of 90%.


Hydrogen cracking G-BOP Test FCAW 



The authors express their thanks to Fapesp and CNPq for financial support of fundamental importance for this work and to the Faculty of Mechanical Engineering of UNICAMP for the indispensable laboratory infrastructure.


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Copyright information

© ASM International 2008

Authors and Affiliations

  • José Hilton Ferreira da Silva
    • 1
  • Hipolito Carvajal Fals
    • 2
  • Roseana da Exaltação Trevisan
    • 2
  1. 1.Federal Center of Technologic Education of the Bahia, Metallurgy CoordinationSimoes FilhoBrazil
  2. 2.Department of Mechanical EngineeringState University of Campinas (UNICAMP)Sao PauloBrazil

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