High-hardness armor welded by CW-GMAW: economic, geometric and CGHAZ analysis

  • Charles H. M. VasconcelosEmail author
  • C. R. L. Loayza
  • Paulo D. C. Assunção
  • Francisco F. B. Junior
  • Paola E. C. Baia
  • Diego J. A. Borges
  • Eduardo M. Braga
Technical Paper


High-hardness steel is widely used in the armor industry due to their mechanical properties that combines hardness and toughness, which generates a great resistance to the impact of projectiles. Almost all applications in the armor industry include the welding of its components; however, several modifications could happen in the microstructure. For instance, one main region involved in the welding performance is the coarse-grained heat-affected zone (CGHAZ), especially in high-hardness steel, due to the formation of highly brittle, non-tempered martensitic. Furthermore, studies concerning the influence of the variations in welding parameters and the addition of cold wire have not been conducted so far. In this paper, we determined the influences of the welding parameters on the economical, geometric and coarse-grained heat-affected zone of the weld beads. In addition, the influences of the cold wire are also shown. To perform the experimental procedure, two parameters were tested: the industrial parameters, used for the conventional steel welding, and the experimental parameters, obtained in this study. The welding velocity and dilution were 150% and 53% higher, respectively. Besides, the deposition rate was 100% greater for the improved parameters with a 50% reduction in the CGHAZ area.


Welding Super steel High-hardness steel Armox 500T Heat-affected zone 



The authors would also like to provide special thanks to the work teams from the Material Characterization Laboratory (LCAM) of the Federal University of Para (UFPA), where all the experimental tests were performed, and special thanks to the Engineering of Natural Resources of the Amazon Graduate Program (PRODERNA) which provided the e-mail corresponds author’s scholarship of CNPq, number 170412/2017-2. CL received a scholarship from CAPES under the supervision of the Partnerships Program for Education and Training (PAEC) between the Organization of American States (OAS) and the Coimbra Group of Brazilian Universities (GCUB), with the support of the Brazilian Ministry of Foreign Affairs’ Division of Educational Topics and the Pan American Health Organization (PAHO/WHO). Special acknowledgments are to TECMETAL for the microstructure analyses.


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Copyright information

© The Brazilian Society of Mechanical Sciences and Engineering 2019

Authors and Affiliations

  • Charles H. M. Vasconcelos
    • 1
    Email author
  • C. R. L. Loayza
    • 1
    • 2
  • Paulo D. C. Assunção
    • 2
  • Francisco F. B. Junior
    • 3
  • Paola E. C. Baia
    • 3
  • Diego J. A. Borges
    • 1
  • Eduardo M. Braga
    • 1
    • 2
    • 3
  1. 1.Programa de Pós-graduação em Engenharia Mecânica (PPGEM/UFPA)Universidade Federal do ParáBelémBrazil
  2. 2.Programa de Pós-Graduação em Engenharia de Recursos Naturais da Amazônia (PRODERNA/ITEC/UFPA)Universidade Federal do ParáBelémBrazil
  3. 3.Faculdade de Engenharia MecânicaUniversidade Federal do ParáBelémBrazil

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