缺陷檢測技術於工業應用上是一種關鍵檢測技術，根據文獻回顧得知，各種缺陷建測技術中，渦電流檢測法可有效應用於檢測導電體之表面缺陷，原理是藉由探頭線圈激勵磁場與導電體內感應之渦電流磁場交互作用，感測線圈會感應缺陷訊號。因操作不易受表面油漬污染影響，且比它種檢測方式強健，現今大量應用於檢測航太、核能及尖端金屬工業之製品。隨著各種科技進步，渦電流感測器之量測解析度及精度日漸提升，現今位置型渦電流感測器可達1微米之解析度，如整合渦電流操作設計原理及其它量測元件，則可應用於不同材質之檢測，如更改探頭線圈架構、採用陣列式激勵線圈及內置TMR或GMR元件等，已衍生眾多創新應用技術。
本論文之研究目標為探討導電待測物之表面缺陷檢測原理及技術，針對渦電流檢測訊號於探頭及缺陷之位置、幾何尺寸及邊緣效應之影響，進行基礎理論及建構雛型之實驗驗證。首先使用電腦輔助工程分析進行數值模擬，軟體平台採用美商ANSYS公司之Maxwell2D/3D®，研究各項設計參數靈敏度，再以暫態模擬分析渦電流於缺陷附近之分布，並解析感應之探頭電壓訊號。最後架設實驗平台以驗證自製之雛型感測器，進行量測已知待測物之表面各種缺陷深度及形狀於探頭阻抗及輸出電壓數據，發現實驗數據及理論分析相符，期望對導電體表面缺陷檢測技術能提供學術參考及工業應用價值。

Defect detection technology is crucial in various industrial applications. Among the various detection methods, eddy current testing (ECT), based on analysis of interactions between probe-excitation field and induced eddy current on the object, is known for effectiveness in surface defects detection in conductive objects. Robust to surface contamination influences, ECT is widely used in aerospace, nuclear energy, and high-end metal industries. Up to date, technology advancement has significantly improved ECT resolution of modern displacement sensors with 1-micron accuracy. Innovations such as modified probe coil structures, array-type excitation coils, and integrated TMR or GMR elements have been available in many new applications.
This study explores detecting surface defects in conductive objects with emphasis on the effects of defects geometry and edge effects on eddy current detection signal. By using ANSYS Maxwell 2D/3D® packages, the distribution of eddy current can be numerically simulated via transient analysis module. In experimental verifications, a prototype sensor is built for detection of surface defects in various channel depths. The results conclude valuable insights for both academic research and industrial applications of ECT sensors in surface-defect detection.

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