Enhancement of microwave nondestructive testing method for the inspection of pipes by optimizing the microwave probe profile

Sasaki, Kota*; Yusa, Noritaka*; Wakai, Takashi ; Hashizume, Hidetoshi*

This study reports the development of a new microwave probe for the nondestructive testing of a pipe. Three-dimensional finite element simulations are carried out to optimize the profile of a microwave probe, whose results show that a probe with elliptic profile enables smaller reflection at the probes as well as much better single-mode propagation inside the pipe than conventional ones. Experimental validations are carried out using a straight brass pipe with an inner diameter of 39 mm and a total length of 2 m. The results of the experiments clearly demonstrate that the new microwave probe provides clearer signals due to simulated rectangular wall thinning.