Application of Paris’ law for estimation of hydrogen-assisted fatigue crack growth

•A method is proposed for estimating rate of Hydrogen-Assisted Fatigue Cracking.•General form of Paris’ law is used.•1-D hydrogen diffusion from crack tip is assumed.•Simulations are in agreement with experimental results on X52, X70–80 and X80 steels.

Based on the general form of Paris’ law a new method is proposed for estimating the rate of cracking of metals under Hydrogen-Assisted Fatigue. It is based on relating the fatigue crack growth rate of hydrogen embrittled metal to the fatigue crack growth rate of the metal without hydrogen embrittlement. One-dimensional hydrogen diffusion is assumed. Simulations using the proposed method on steel types X52, X70–80 and X80 are in agreement with published experimental tests results. The new method obviates numerical modelling of crack propagation and much reduces the computational costs.