Efecto de la fragilización inducida por hidrógeno interno en la velocidad de crecimiento de grieta por fatiga de la zona de grano grueso en una soldadura de acero 2.25Cr1Mo
- 1 Grupo SIMUMECAMAT, Escuela Politécnica de Ingenieros de Gijón
ISSN: 2792-4246
Year of publication: 2022
Issue: 3
Pages: 231-236
Type: Article
More publications in: Revista española de mecánica de la fractura
Abstract
The effect of hydrogen in the fatigue crack growth rate of the coarse grain zone of a 2.25Cr1Mo steel weld is analysed in this work. The microstructure of the coarse grain zone was simulated using a heat treatment able to provide a steel with a grain size and hardness similar to the ones of a real weld. The crack growth rate was measured using compact tension (CT) specimens that were tested both in the absence of hydrogen (AR: as received) and after hydrogen pre-charging using a pressure reactor (19.5 MPa and 450ºC for 21 hours). The influence of frequency was analysed using different values (f = 10Hz, f = 0.1Hz and f = 0.05Hz). Also, two load ratios (R = 0.1 and R = 0.5) were used to assess their influence. The embrittlement produced by the internal hydrogen is clearly noticed at the beginning of the fatigue growth rate test (∆K = 30MP√m), obtaining higher values than without hydrogen. In addition, this effect becomes more notoriuos as the test frequency decreases or the load ratio increases.