A Hybrid Phased Array Ultrasonic Testing Methodology for A1106 High-Manganese Steel Welds Using DMA Longitudinal and Creep Wave Techniques

High-manganese steels such as A1106 are increasingly used in critical industrial applications due to their excellent wear resistance and mechanical properties. However, their coarse grain structure, high acoustic attenuation, and strong scattering behavior make ultrasonic inspection of welds particularly challenging. Conventional shear wave Phased Array Ultrasonic Testing (PAUT) often results in poor signal-to-noise ratio, unstable beam propagation, and inconsistent detection of planar and transverse-oriented defects. This paper presents a hybrid, material-specific PAUT methodology developed for the inspection of A1106 high-manganese steel welds using Dual Matrix Array (DMA) probes configured with longitudinal angle beams and creep wave techniques. Longitudinal wave inspection demonstrated improved penetration, signal stability, and reliable volumetric coverage, while creep wave inspection enhanced sensitivity to near-surface regions, fusion lines, and weld toes. Challenges associated with wedge delay calibration were addressed through witnessed demonstrations. Omission of wedge delay correction, combined with systematic depth compensation, improved sizing repeatability without compromising inspection effectiveness, consistent with the intent of ASME Section V. Complementary multi-face shear wave PAUT was applied for defect characterization and sizing validation. The results confirm that a demonstrated hybrid PAUT approach is essential for reliable inspection of acoustically difficult high-manganese steel weldments.