Ultrasonic arrays for quantitative nondestructive testing an engineering approach

Abstract

The Ultrasonic Pulse-Echo inspection method is extremely capable of detecting cracks that limit the structural integrity of loaded technical components and systems. However, the applied principles of ultrasonic material testing do not in general allow the characterization of flaws and the required measurement of crack dimensions. Appropriate wave field data sampling at the scanned surface with the subsequent field reconstruction improves both the resolution and the contrast sensitivity of inspection results. We use arrays with elements adapted for the inspection task with an optimized arrangement and element apertures of point source character. First results have been received applying linear arrays that are promising for the quantitative assessment of flaws by high-resolved high contrast imaging of inspection results in real-time

Experimental Investigation on the Corrosion Detectability of A36 Low Carbon Steel by the Method of Phased Array Corrosion Mapping

“…Phased array ultrasonic testing (PAUT) can scan a large area to detect general and localized corrosion [7], but it still faces the same ultrasonic inspection limitation that exceeds the standard recommended ultrasonic testing temperature of 52 • [8] when carrying out on-stream corrosion monitoring at some piping operating temperatures greater than 200 • C.…”

The Effect of the Position Determination Error for Flexible Linear Array Elements on the Tomogram Focusing

“…In recent years, the multi-element acoustic arrays found a broad range of applications for inspection of industrial components [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 ]. Among the advantages in comparison with the single-element transducers, it is possible to mention the following: Much faster inspection process; Easiness in reading ultrasonic image; Imperfection may be immediately detected and evaluated; Several types of inspection may be realised using the same equipment; Possibility to reconstruct 2D and 3D images [ 10 , 11 ]; Possibility to gather inspection data for large inspection zone from a single transducer position.…”

“…Focusing may be realised by setting delay laws for each element of the acoustic array in order to direct the maximum acoustic energy to the certain point of an inspected object structure [ 1 ]. Additionally, focus may be achieved synthetically by shifting of A-scans during the post-processing stage [ 7 , 8 , 9 , 10 , 11 ]. There are several methods of reconstruction of the acoustic signals obtained from the acoustic array used in ultrasonic non-destructive testing.…”

Studies of Angular Resolution for Acoustic Arc Arrays

“…With computers emerging there appeared the possibility to realize complex computations, providing complex algorithms to manipulate multi-element acoustic arrays. The most widespread method is the total focusing method (TFM), named the "Golden Standard", as well as its modifications [2][3][4][5][6][7][8][9][10][11][12]. In the majority of industries such as aviation, aerospace and nuclear, the ultrasonic testing of products is very often performed with direct contact or with the application of a prism which is located between the acoustic array and the object under inspection.…”