Analytical model of tilted driver–pickup coils for eddy current nondestructive evaluation

Cao Bing-Hua^{1, 2}, Li Chao^{1, †}, Fan Meng-Bao^{2, 3}, Ye Bo⁴, Tian Gui-Yun⁵

(color online) Variations of mutual inductance with frequency for (a) φ = 0°, (b) 45°, (c) 60°, and (d) 90°.