Abstract
If the surface of specimen is rough, or the material is cold or hot in the narrow spot, the application of a couplant is impossible. Therefore, non‐contact air coupled ultrasonic testing (NAUT) is applied here for previously compensating the inspection method of ultrasonic wave. If NAUT is applied, the inspection of ultrasonic wave is possible even without a couplant. In addition, the transmission/reception of ultrasonic wave is possible in a stable state. Therefore, the non‐contact test method including the inspection of a part with rough surface will be elsewhere. The realisation of exact high efficiency spot welding inspection with increases in quality, yield and efficiency of materials using NAUT is also possible. Therefore, the effect of NAUT to perform the inspection is known. Thus, the advantages of NAUT are highlighted piece by piece through the spot welding and CFRP inspection. The paper also reported the results of waveform analysis. As a result, the specimens of spot welding and CFRP using the NAUT technique have been made and the thickness and position of the specimen, regardless of the degree of spot welding in the ultrasound transmission, were the highest; the specimen of CFRP is also a part of the faulty part and does not increase the amplitude of the waveform. Whether it reduces the presence of interlayer detachment was unknown, and the practical use of NAUT has confirmed this.
This work was supported by the Korea Research Foundation funded by the Korea government (grant no. 2009‐0075213).