Analysis of Flaw Detection Sensitivity of Phased Array Ultrasonics in Austenitic Steel Welds According to Inspection Conditions

Abstract

The anisotropy and inhomogeneity exhibited by austenitic steel in welds poses a challenge to nondestructive testing employing ultrasonic waves, which is predominantly utilized for the inspection of welds in power plants. In this study, we assess the reliability of phased array ultrasonic testing (PAUT) by analyzing the flaw detection sensitivity of ultrasonic beams in anisotropic welds, based on the inspection conditions. First, we simulated the sectorial scan technique, frequently employed for the inspection of actual welds, while taking into account the ultrasonic wave mode, frequency, and shape and position of a flaw. Subsequently, we analyzed the flaw sensitivity by comparing A-scan signals and S-scan results. The sensitivity analysis results confirmed the detection of all flaws by considering at least two inspection methods based on the shape and position of the flaw. Furthermore, we verified our model by performing an experiment under the same conditions as the simulation and found that the results were in agreement. Hence, we find that the simulation modeling technique proposed in this study can be utilized to develop suitable inspection conditions, according to the flaw characteristics or inspection environment.

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

“…After considering the aforement issues and conducting several trials, a preferable testing combination was ultimatel covered. The testing uses a high-temperature-resistant wedge [48] and focuses on limitin tact time during detection, while the phased array probe uses a general-purpose probe [49]. The water-soluble couplant is also replaced with high temperature-res oil [50].…”

“…A schematic diagram of the phased array corrosion mapping experimental se shown in Figure 4 below, where the heat treatment equipment is used to heat the men to a specific temperature required for the experiment, and the PAUT equipmen lects the data and further transmits them to a computer for interpretation. The testing uses a high-temperature-resistant wedge [48] and focuses on limiting contact time during detection, while the phased array probe uses a general-purpose 5L64 probe [49]. The water-soluble couplant is also replaced with high temperature-resistant oil [50].…”

Twenty Years of Progress in Microstructure Modelling for Ultrasonic Testing, from Shielded Metal Arc Welding to Gas Tungsten Arc Welding: An Analysis for Future Developments

“…These ideas to describe an acoustically inhomogeneous anisotropic material continue to be tested regularly in various welding configurations in 2D situations, often using ray tracing models in 2D situations [43,44]. Material description is always the first step of a good UT simulation, even in the newest studies with modern tools, using, for example, phased array ultrasonic testing (PAUT) and a simulation code like CIVA [45].…”

Measurement of Thinned Water-Cooled Wall in a Circulating Fluidized Bed Boiler Using Ultrasonic and Magnetic Methods

“…(3 Figures 2 and 3 show the result of calculating H y for the depth of the defect d in the range of 0~3 mm and position x p in the range of −15-15 mm using Equations (1)- (5); where m was assumed as 2π × 10 −4 [H/m], relative magnetic permeability of the ferromagnetic material µ = 500, the lift-off h = 1 mm, and the width (D) and width (W) of the magnetic poles were assumed to be 10 mm. Large changes of the magnetic flux intensity on the defect size with different depths are shown in Figure 2.…”

“…Phased array ultrasonic testing (PAUT) has been developed to reduce mechanical errors while scanning the probe on the specimens and signal enhancement. It provides excellent results of damage detection and quantitative evaluation of the damage size, such as depth and length [4,5]. However, the UT and PAUT methods require continuous supplement of the coupling materials such as water for the propagation of ultrasonic wave between the probes and the tube, and the surface of the tube should be cleaned before the inspection.…”