Methods of measuring ultrasonic wave velocity in an elastic sample require data on the thickness of the sample and/or the distances between the transducers and the sample. The uncertainty of the ultrasonic wave velocity measurements generally depends on that of the data available. Conversely, to determine the thickness of a material, it is necessary to have a priori information about the wave v...

recently, the al2o3–tio2–zro2 system has found valuable applications, particularly, as a support for nox storage–reduction (nsr) catalysts. nanocomposite powders were prepared from the co-precipitation method in inorganic precursors. the behaviors of mixed oxide nanoparticles under ultrasonic irradiation, such as dispersion, and crushing were studied. phase transformations, crystallite size, an...

Time-of-flight diffraction method (ToFD) is an amplitude-independent sizing method which is based on the measurement of time-of-flight of defect tip diffracted waves. Although ToFD can measure through-wall length of defect accurately, this method is not capable of measuring horizontal defect size. In this paper, a new ToFD method for evaluating horizontal planar defects is presented. The finite...

This paper proposes a continuous leakage location method based on the ultrasonic array sensor, which is specific to continuous gas leakage in a pressure container with an integral stiffener. This method collects the ultrasonic signals generated from the leakage hole through the piezoelectric ultrasonic sensor array, and analyzes the space-time correlation of every collected signal in the array....

In this paper, the non-destructive testing methods are analyzed in view of their usability in evalulation of the interlocking paving blocks’ compressive strength. Ultrasonic pulse method and impact method (Schmidt impact hammers) were chosen for testing. Testing methodology and way of the results processing considering requests of the national and European standards are described there. In addi...

In order to detect whether there is a base gap between the explosive charge and the inner cone of a shell and ensure its fighting performance, this paper puts forward an ultrasonic inspection method of base gap based on the principle of conservation of sound flux in propagation and according to the special construction of the shell. Inspection of artificial base gap on the inner cone and actual...

Air – coupled ultrasonic investigation possess a great potential for investigation of aerospace composite materials, because it avoids disadvantages caused by immersion or contact techniques. In the work the test sample of the GLARE3-3/2 composite material with artificial delamination type defect was investigated. Numerical and experimental investigations using focussed air – coupled ultrasonic...

The Laser ultrasonic technique (LUT) is an interesting method to perform inspection of large aeronautical panels of complex shapes. Its non-contact feature avoids coupling problems and could improve the efficiency of the NDT inspection in the composite manufacturing industry. If the ultrasound generation process is well understood in metallic samples, the application of the technique in composi...

The Ultrasonic transit time method is well established to measure the volumetric flow rates of liquids and gases. In most applications the measured flows are turbulent. The ultrasonic measurement technique has advanced to a level of accuracy where the turbulence of the measured media is the main source of fluctuations in the measured flow value. Experiments on flowmeters with different diameter...