Micro defect identification by weak magnetic signal excited by magnetic field controlled in time and space

2022 Fiscal Year Final Research Report

• Project/Area Number: 17K06467
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Measurement engineering
• Research Institution: The University of Shiga Prefecture
• Principal Investigator: SAKUTA Ken 滋賀県立大学, 工学部, 教授 (70221273)
• Project Period (FY): 2017-04-01 – 2023-03-31
• Keywords: 磁場計測 / SQUID

Outline of Final Research Achievements

Today, detection of defects including foreign articles is a very important issue in industrial products. We have investigated a defect detecting system by measuring magnetic signals generated by applying an external excitation magnetic field using a super-sensitive magnetic sensor based on a superconducting quantum interference device (SQUID).
We investigated the generation mechanism of the excitation magnetic field and its optimization, improvement of the SQUID flux locked loop circuit, which is the main detection device, and the noise canceling system, and, as a results, were able to improve the performance of each part.

Free Research Field

計測工学

Academic Significance and Societal Importance of the Research Achievements

ますます微細化が進む各種製品において、その傷や異物混入など欠陥検出は非常に重要な課題である。これらに対応する一つの手法として、磁気検出を利用したシステムの性能向上は、欠陥検出技術の幅を広げるものである。
さらに、ＳＱＵＩＤ　ＦＬＬ回路の簡便なデジタル回路化は、ＳＱＵＩＤの利用範囲を広げることにつながり、より高感度化への試みを容易にするものと考えられる。また、励起信号の時間的・空間的制御技術および雑音低減技術は、欠陥検出に限らず、様々な計測領域で重要な要素技術と考えられる。