A world-first metamaterial that generates ultrasound waves has been developed, enabling the simultaneous detection of cracks and defects in older structures, such as aging buildings, aircraft, and steel bridges. This technology is expected to serve as a foundational technology in various fields, including industrial nondestructive testing and medical ultrasound.

The research team of Senior Researcher Minwoo Kwon of the Nano Display Laboratory of the Nano Convergence Equipment Research Division of the Korea Institute of Machinery and Materials (President Seokhyun Ryu) and the research team of Professor Yunyoung Kim of the Department of Mechanical Engineering at Seoul National University have developed a metamaterial that generates circularly polarized ultrasound that can simultaneously detect defects in structures such as cracks in old buildings or aircraft, and published the related research results in the prestigious journal Nature Communications (IF:16.6).

The metamaterial developed by a joint research team from the Korea Institute of Machinery and Materials and Seoul National University was made by drilling a series of holes in a large-area aluminum metal. The research team adjusted the shape and spacing of the holes in the metamaterial to pass a straight-line ultrasound through the metamaterial and convert it into a circular vibration ultrasound.

Conventional non-destructive testing methods send ultrasonic waves that vibrate in a straight line to a structure to detect structural defects. However, such testing is difficult to investigate all areas inside the structure, requiring at least two or more inspections. This technique has limited use due to its long inspection time and low accuracy in the results.

Researchers have successfully created the world's first circular ultrasound using metamaterials. This technology significantly reduces inspection time and detects structural defects with a single test and 12 times higher accuracy than existing technologies, and is expected to lead to improved industrial productivity, including non-destructive testing.

Minwoo Kwon, a senior researcher at the Korea Institute of Machinery and Materials, said, “This is a new concept technology that can improve the defect detection performance of existing ultrasonic inspection technology,” and added, “It will not only be used for future imaging diagnosis, but will also change the paradigm of medical ultrasound technology beyond industrial non-destructive testing, such as controlling fine particles in displays and drugs.”

Meanwhile, this research was conducted with support from the Ministry of Science and ICT and the National Research Foundation of Korea through the Mid-career Researcher Support Project and the Global Frontier Project.