Creation of Acoustic Resonance Imaging Technique and Challenge to Visualize the Quality of Thin Polymer Layers

2022 Fiscal Year Final Research Report

• Project/Area Number: 21K18664
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 18:Mechanics of materials, production engineering, design engineering, and related fields
• Research Institution: Tohoku University
• Principal Investigator: Tohmyoh Hironori 東北大学, 工学研究科, 教授 (50374955)
• Project Period (FY): 2021-07-09 – 2023-03-31
• Keywords: 音響共鳴 / 超音波映像法 / 薄層 / 品質 / 密着性 / 塗装膜 / フォトレジスト膜 / 接着層

Outline of Final Research Achievements

An innovative acoustic resonant imaging technique that utilizes the acoustic resonance occurred when sound is reflected from or transmitted through thin layer has been developed, and the developed technique makes it possible to obtain two-dimensional information on the acoustic properties and thickness of the layer. A new ultrasonic measurement principle has been developed to evaluate any of the six parameters of acoustic impedance, density, sound velocity, thickness, and adhesion between thin layer and the media above and below the layer depending on the purpose. A unique system that calculates and analyzes the ultrasonic waveforms taken from existing ultrasonic imaging system has also been developed. With the developed measurement principle and the system, the thickness of coating, degradation of polymer film, or the quality of adhesive layer could be successfully visualized as high-resolution two-dimensional information.

Free Research Field

材料力学および機械材料関連

Academic Significance and Societal Importance of the Research Achievements

本研究課題の遂行により実現した音響共鳴映像法は、従来、点計測であった音響共鳴計測法を面計測へと拡張し、これにより薄層の音響物性値と膜厚の2次元情報を取得可能にしたものである。開発した手法は、燃料電池用電解質膜、あるいは各種輸送機器の組み立てに利用される接着剤など、次世代材料システムの性能を向上させ、安全性を担保するために欠かせない、様々な高分子フィルム・膜・層の革新的超音波検査に活用でき、その社会的意義は大きい。