透射式涡流渗透深度的仿真与实验

Simulation and experiment of penetration depth of transmission eddy current

线圈尺寸的设计和激励频率的选择对于涡流检测至关重要。针对作为涡流检测行业标准的标准渗透深度方程没有考虑到线圈尺寸的影响问题,建立了透射式涡流检测的有限元仿真模型,研究了不同激励频率和不同尺寸探头对透射式涡流渗透深度的影响,并通过实验证实了仿真分析的有效性。仿真与实验结果表明:激励频率较高时,透射式涡流可检测到缺陷的深度大于标准渗透深度;较高的激励频率能保证更好的检测效果,且受线圈尺寸影响较小。

Design of coil size and selection of excitation frequency are essential for eddy current testing.The standard penetration depth equation as the standard for eddy current testing does not take into account the effect of coil size.Aiming at this problem,a finite element simulation model for transmission eddy current detection is established.The influence of different excitation frequency and different size probe on penetration depth of transmission eddy current is studied.The validity of simulation analysis is proved by experiments. Simulation and experimental results show that：When the excitation frequency is high,the transmission eddy current can detect the depth of the defect is greater than the standard penetration depth,and the higher excitation frequency can guarantee better detection effect; higher excitation frequency can ensure better detecting effect,and it is less affected by coil size.