Ultrasound computed tomography for material inspection: principles, design and applications

Abstract

The non-destructive testing based on an ultrasound computed tomography (UCT) technique has attracted the attention of the industrial and medical area due to its excellent capabilities in several applications. The utilization of UCT has provided a prodigious benefit for analyzing and monitoring the condition of material. This paper presents a review of ultrasound computed tomography for its applications in construction, process control, medical, temperature monitoring, agriculture and food industry. The main elements of UCT including ultrasonic sensing modes, types of ultrasonic waves and the design of measurement system are discussed. This paper also presents the mathematical modelling for the ultrasonic parameters employed during the measurement process, such as attenuation coefficient, acoustic impedance, wave velocity, frequency value and wave amplitude. The concept of analytical image reconstruction algorithm and the optimization technique for reconstructing the material image are also expounded in this paper. Selected articles in previous researches are discussed and elaborated. Trends and future outlook for the UCT technique are also presented. This paper fulfills the need of review paper for the principle and applications of ultrasound computed tomography for material inspection. It is envisaged that the information gathered in this paper will be a valuable source of information for researchers working in this topic.