微細平面コイルによる金属体極表面の性状検出と初期劣化の推定に関する研究

讨论了利用微平面线圈非接触测量金属近表面物理性质（电导率和磁导率）的可行性，并通过分析和实验验证了其精度。结果表明，该方法为金属结构的劣化检测提供了丰富的信息.本课题的主要研究成果如下：1.弯折平面型探头的制作我们利用刻蚀技术研制了13^× 13mm的微平面型线圈，并利用阻抗分析仪制作了测量系统，用于电磁特性的测量。可以测量频率高达500kHz的阻抗。2.微平面线圈形状的检验为了提高电导率估算的灵敏度，我们对微弯折线圈的形状进行了检验。显然，具有较大节距的曲折图案更适合于测量具有较高电导率和厚度的物体。通过不同平面线圈的电导率测量验证了该关系.分析和检测模型我们考虑了微弯测头的二维模型，可以通过分离变量来分析系统。因此，我们可以用反问题来估计金属的电导率。采用非接触式测量方法，可以在30%的精度范围内对电导率进行测量.疲劳评估的模型实验以陶瓷涂层复合金属材料为模型材料。本文试图估算金属与陶瓷之间粘结剂的电导率。用这种方法可以估计电导率，电导率的变化可以提供疲劳的信息。

We discussed the feasibility of estimating physical properties (conductivity and permeability) on near-surface of metals without contact by using micro planar type coil and examined its precision by analytical and experimental tests. As a result, the measuring approach gives much information of inspecting deterioration of metallic structure. The achievements of the research project are follows,1. Fabrication of meander planar type probeWe developed the micro planar type coil of 13^*13mm area by etching techniques and made the measuring system to estimate electromagnetic properties by using impedance analyzer. It is possible to measure impedance on the frequency up to 500kHz.2. Examination the shape of the micro planar coilWe examine the pattern of the micro meander coil to improve the sensitivity of estimating conductivity. It is clear that the meander pattern with larger pitch is better to measure the object with higher conductivity and thickness. We verified the relationship by measuring conductivity by various planar coils.3. Analysis and inspection modelWe consider the 2D mode for micro meander probe and could analyze the system by the separation of variables. As a result, we can estimate the conductivity of metal as inverse problem. We can evaluate the conductivity within 30% precision by non-contact method.4. Model experiment for evaluating fatigueWe consider the compound metallic material with ceramic coating as model material. We try to estimate the conductivity of bonding agent between metal and ceramic. It is possible to estimate the conductivity by our method, then the variation of conductivity may give the information of fatigue.