Inspenet, August 29, 2023.
The Korea Research Institute of Standards and Sciences (KRISS) and Korea University (KU) have collaborated on the development of an innovative lead-free ultrasonic sensor designed to carry out inspections on large structures, particularly pipelines. of water supply.
The technique of using guided waves to inspect water supply pipes is a non-destructive testing method that can detect problems such as corrosion . One of the main advantages of this approach is its ability to cover a wide range with minimal use of sensors.
Despite this, most guided wave sensors are built with piezoelectric materials that contain lead, a dangerous metal. However, due to the dangerous nature of lead, its use is restricted by Europe’s eco-certification system known as RoHS.
Lead-free ultrasound sensor: friendly to the environment
In order to address these concerns, the KRISS-KU research team has developed guided wave sensors using lead-free piezoelectric materials. These sensors not only eliminate health and environmental risks , but also exhibit superior performance compared to lead-based alternatives.
The newly conceived sensor is omnidirectional, emitting signals evenly in all directions. It operates in shear wave ultrasonic mode, making it especially effective for inspecting pipelines, even when the water flow is constant and without loss of power.
To optimize the effectiveness of the shear wave mode, the research team redesigned the shape of the sensor component, giving it a unique trapezoidal configuration. This design, combined with the lead-free materials, resulted in a significant increase in output intensity, exceeding traditional lead-based sensors by more than 15%.
This advance is anticipated to transform pipeline inspection methods. Instead of periodic spot inspections, it is possible to achieve continuous monitoring without the need for human intervention over a larger area. This methodology is already being implemented in English-speaking and European countries.
Dr. Hong Min Seung, research leader at KRISS, highlighted that the lead-free sensor is built with environmentally friendly materials, which ensures its safe use in pipelines without impacting the surrounding environment or the quality of the product. water. In addition, this technology will increase the competitiveness of national companies in the global field of non-destructive testing.
The results of this research have been published in the journal Ceramics International .