Abstract:Aiming at the problem of hydrogen embrittlement caused by diffusion and accumulation of hydrogen in materials, a characterization method based on eddy current signal is proposed. Taking the electrochemical hydrogen charging sample as the research object, firstly, the hydrogen distribution of the sample in the electrochemical hydrogen charging process is calculated based on Fick's law. Then, based on the principle of electromagnetic induction, the eddy current detection finite element model of material hydrogen embrittlement under different hydrogen distributions is established by using COMSOL multiphysics. The distribution of induced eddy current field of the sample excited by time-harmonic electromagnetic field and the electromagnetic field diagram of the detection coil are analyzed by numerical calculation. The in-situ tensile test quantitatively characterized the degree of hydrogen embrittlement. The correlation mechanism between hydrogen embrittlement index and eddy current response signal was analyzed for experimental verification. The results show that the degree of hydrogen embrittlement of metal materials is closely related to the hydrogen content, and the eddy current signal under the action of a time-harmonic electromagnetic field is linearly related to the degree of hydrogen embrittlement, which verifies the effectiveness of the finite element model for eddy current evaluation of material hydrogen embrittlement.