Optimization of Ultrasonic Testing System Applicable to High Manganese Steel Rails

High manganese casting steel rails are currently used at crossing points of railway tracks due to their high damage tolerance. However, conventional ultrasonic testing (UT) methods cannot be effectively applied to these rails because of their large crystal grains and casting defects. This study proposes a new ultrasonic imaging method that utilizes aperture synthesis and advanced signal processing techniques. The applicability of the proposed method was evaluated through experiments involving high manganese steel rails with artificially created surface cracks. The results demonstrated that the ultrasonic images were significantly improved, allowing for a better observation of the distributions of large defects. However, the method struggled with detecting small cracks, which may remain hidden, and planar cracks could be misidentified as point-shaped defects. The findings suggest that while the new technique shows promise for enhancing defect detection in high manganese steel rails, further investigation is needed to ensure its efficacy in real-world applications.