Geometric optimization of a differential planar eddy currents probe for non-destructive testing

• Seven geometrical parameters of an eddy currents sensor probe were defined.
• A methodology to evaluate the different sensor probe designs is described.
• The effect of each geometrical parameter is discussed based on simulation results.
• Several designs were prototyped and used to validate the simulation results.
• Two optimized designs were presented, evaluated experimentally and compared.

The influence of the geometrical parameters of an eddy currents planar probe intended for non-destructive testing is reported in this paper. Finite element modeling simulations were used to evaluate the effect of each geometrical parameter on the probe response amplitude and spatial discrimination while testing an arbitrary defect. A representative set of probes was produced and used to experimentally validate the simulation study. The reported results show that modifications of the studied parameters can substantially improve the probe performance targeting specific testing requirements. Additional probes were produced using a parameters combination optimized for two different testing situations. It was also shown that the modification of the defects properties does not substantially modifies the relative effectiveness of the additional probes produced.