Development of Acoustic Microscope for High Attenuated and Anisotropic Inconel Alloy Welding Part

1995 Fiscal Year Final Research Report Summary

• Project/Area Number: 06452332
• Research Category: Grant-in-Aid for General Scientific Research (B)
• Allocation Type: Single-year Grants
• Research Field: Material processing/treatments
• Research Institution: TOHOKU UNIVERSITY
• Principal Investigator: MIHARA Tsuyoshi Tohoku University, Faculty of Engineering Associate Professor, 工学部, 助教授 (20174112)
• Project Period (FY): 1994 – 1995
• Keywords: Inconel Alloy / Acoustic Microscope / Hg Coupler / Welding / Velocity Measurement / V(z) Curve / Local Velocity

Research Abstract

Since ultrasonic inspection depend strongly on the an isotropy in ultrasonic velocity of structural materials, an isotropy in ultrasonic velocity must be investigated. Most suitable measurement system for this an isotropy is Line-focus-beam Acoustic Microscope because anisotropic behavior has complicate and local distribution.However, Acoustic Microscope cannot usually applied for many anisotropic materials because anisotropic materials apt to show high attenuation. In this research, then, we develop the new Acoustic Measurement system for high attenuated materials by using Hg coupler instead of conventional water coupler. New types of acoustic lens and scanner were developped for Hg coupler and V(z) curve for stainless steel and inconel alloy were obtained which cannot measure by water coupler. By using these Acoustic Microscope system, acoustic Image near welding part of inconel alloy were clearly observed and quantitative velocity dependence of ultrasonic propagating direction were measured by Hg coupler. As the results, developped Hg coupler Acoustic Microscope system was useful for acoustic measurement of high attenuated materials.