Efecto del tratamiento térmico post-soldadura en la fragilización por hidrógeno de uniones soldadas de acero CrMoV mediante el uso del ensayo small punch

  1. M.M. Llera 1
  2. A. Zafra 2
  3. S. Otero 1
  4. G. Álvarez 1
  5. I.I. Cuesta 3
  6. C. Rodríguez 1
  1. 1 SIMUMECAMAT Research Group, Universidad de Oviedo, Edificio Departamental Oeste, 7.1.10. Campus Universitario, 33203 Gijón, Principado de Asturias, Spain
  2. 2 Department of Civil and Environmental Engineering, Imperial College London, London, SW7 2AZ, United Kingdom
  3. 3 Structural Integrity Group, Universidad de Burgos, Escuela Politécnica Superior, Avd. Cantabria s/n 09006 Burgos, Spain
Revista:
Revista española de mecánica de la fractura

ISSN: 2792-4246

Ano de publicación: 2023

Número: 6

Páxinas: 55-60

Tipo: Artigo

Outras publicacións en: Revista española de mecánica de la fractura

Resumo

This paper analyses the behavior in hydrogen environment of the characteristic zones (weld metal, heat affected zone and base metal) of a welded CrMoV joint before and after a post-welding heat treatment (PWHT) that consisted of an annealing at 705 °C for 10 hours. For this analysis, both permeation tests and miniature punch tests (small punch test, SPT) in hydrogen environment (in-situ tests) have been used. The hydrogen charge has been carried out in both cases by electrochemical methods, using as an electrolyte a solution 1 M H2SO4 + 0.25 g/L As2O3, and a current density of 1 mA/cm2 . The effect of hydrogen on the different materials was evaluated through the definition of hydrogen embrittlement indices (HEI) based on two characteristic parameters of the SPT test. The results obtained once again demonstrate the applicability of the SPT test in the mechanical characterization of welded joints, and in the quantification of the embrittlement effect of hydrogen when tests are carried out in the presence of this element (in-situ H-charging tests). The PWHT is able to homogenize the mechanical behaviour of all the regions of the welded joint, also managing to improve its behaviour in the presence of hydrogen.