A straightforward simulation method is desired for the reliable nondestructive ultrasonic testing (UT). The target models for the UT become more complicated than ever, such as dissimilar welding parts in nuclear power plant or debonding parts of reinforced steels in concrete material. In this study, a time domain simulation tool for ultrasonic wave propagation in heterogeneous and anisotropic materials w ith a complex outer surface is developed by combining the elastodynamic finite integration technique (...
英字タイトル:
Image-based Simulation of Wave Propagation and its Application to Ultrasonic TestingMember

The use of ultrasonic arrays for non-destructive testing has been widely spread in recent years. As an array imaging method, we propose the full-waveform sampling and processing (FSAP) technique that utilizes a complete set of signals of all combinations of transmission and reception elements. The ultrasonic beam is synthesized from the signal set by the post-processing with the GPU calculation. In this study, pipes and reinforced steel bars in concrete material were reconstructed with the FSAP. Since th...
英字タイトル:
High-speed Ultrasonic Imaging of Steel Bars and Pipes in Concrete using Low Frequency Array Transducer

本稿では、最近の諸外国、特にヨーロッパに焦点をあて、NDE4.0の動向についてサーベイする。特に、NDEデータの共有・交換は、今後の日本にとって重要なものとなるだろうから、少し詳しく述べたい。...

The ultrasonic testing (UT) of a dissimilar metal welding part is difficult due to the acoustic anisotropy and local heterogeneity. The ultrasonic wave in the weld is skewed along crystallographic directions and scattered by metal grain boundaries. Here we propose a straightforward UT simulation tool to predict wave propagation in the weld. The tool is based on the finite integration technique (FIT) and the image-based modeling. In our simulation, a picture of a specimen with a V-groove weld is scanne...
英字タイトル:
Image-based Simulation of Wave Propagation in Dissimilar Metal Welding Part and Its Verification

Guided wave has been applied to a wide variety of non-destructive testing for a plate, bar and pipe, among others. In this study, we propose a wireless sensing system for the guided wave testing in structural components. The three-dimensional motion of the structural component can be visualized using the measured guided waves at a fixed position, which are individually excited at various positions. This method is based on the elastodynamic reciprocity theorem. Here, the validity of the visualization met...
英字タイトル:
Visualization of Guided Wave Excited with Hammer and Identification of Propagation Mode

An ultrasonic measurement method has been developed to determine the crystal growth angle of a unidirectional solidification material by using an ultrasonic array probe. The crystal growth direction of a unidirectional solidified nickel based superalloy are derived within an error of ±5 degrees by evaluating wave height levels of echoes measured with focal laws of each assumed crystal growth angle. Moreover, high precision ultrasonic testing is realized based on the focal laws considering the acoustic anis...
英字タイトル:
Development of Ultrasonic Phased Array Testing Method for Unidirectional Solidification Materials