Ultrasonic phased arrays is a novel technique for generating, receiving and imaging ultrasound. PAUT use multiple ultrasonic elements and electronic time delays to create beams by constructive and destructive interference. As such, it offer significant technical advantages for weld testing and plant monitoring over conventional ultrasonic as phased array beams can be steered, scanned, swept and focused electronically from a fixed probe position. Beam steering permits the selected beam angles to be optimized ultrasonically by orienting or focusing them perpendicular to the predicted discontinuities. Phased arrays allow real-time control of three important ultrasonic probe parameters: Focal distance & Beam angle: continuously and dynamically adjustable, Focal spot size: dynamical-ly adjustable.
- Multiplexing allows fast displacement of ultrasonic beam within probe
- Main benefits of ultrasonic phased arrays:
- High-speed inspection using single-axis scans instead of conventional raster scan
- Near-optimal focal length and focal spot for various areas of complex parts or thick components
- Small, simple probe assembly with multiple beams from a single probe
- Better detection in austenitic materials and dissimilar metal welds
- Alternative to Radiographic imaging.