Fully flexible thin-film ultrasonic array for use in industrial NDE applications
B Rocks, D Irving, F Gaudenzi and D A Hughes
Novosound Ltd, Biocity, Motherwell, UK
Ultrasonic inspection is the go-to tool for many industrial NDE applications. Ultrasonic arrays have been employed in NDE since the 1980s. However, with the rise of computer-generated, complex, geometrical structures, the demand for arrays with the ability to conform to these structures is more pressing than ever before. The work here reports on the development of a truly flexible ultrasound array that allows uninspectable objects to be ultrasonically inspected.
A novel, thin-film, piezoelectric material is deposited onto a flexible substrate using reactive sputtering of a metal-oxide-based alloy. Additive manufacturing processes are then employed, which allow for the mass manufacture of flexible arrays with consistent acoustic output and build quality, capable of operating in the region of 5-100 MHz. The arrays are subsequently demonstrated and tested on a variety of materials with varying geometries such as composite structures and metallic turbine blades. Moreover, these arrays are also demonstrated as permanently installed sensors, providing a solution to improved continuous monitoring with more information available to the industry.
Data presented here includes sensitivity analysis and performance of a 64-element 10 MHz ultrasound array. This was carried out using a DPR500 (JSR Electronics) pulse-echo system with 140 V excitation and, subsequently, with a commercial NDT instrument for full phased array imaging. Preliminary testing has shown that fully flexible arrays could be the next step in imaging and monitoring complex structures for various industrial applications. Early results have shown an operation of 7-10 MHz with a bandwidth of 67%. Images have been obtained from scanning test objects, comprising metallic and carbon-composite materials, using industry-standard equipment showing ability to inspect complex structures with high resolution across curves, bends and twists at varying thicknesses.
Further work will concentrate on the refinement of both the proprietary material and array manufacture process to improve the signal output and array sensitivity.
A novel, thin-film, piezoelectric material is deposited onto a flexible substrate using reactive sputtering of a metal-oxide-based alloy. Additive manufacturing processes are then employed, which allow for the mass manufacture of flexible arrays with consistent acoustic output and build quality, capable of operating in the region of 5-100 MHz. The arrays are subsequently demonstrated and tested on a variety of materials with varying geometries such as composite structures and metallic turbine blades. Moreover, these arrays are also demonstrated as permanently installed sensors, providing a solution to improved continuous monitoring with more information available to the industry.
Data presented here includes sensitivity analysis and performance of a 64-element 10 MHz ultrasound array. This was carried out using a DPR500 (JSR Electronics) pulse-echo system with 140 V excitation and, subsequently, with a commercial NDT instrument for full phased array imaging. Preliminary testing has shown that fully flexible arrays could be the next step in imaging and monitoring complex structures for various industrial applications. Early results have shown an operation of 7-10 MHz with a bandwidth of 67%. Images have been obtained from scanning test objects, comprising metallic and carbon-composite materials, using industry-standard equipment showing ability to inspect complex structures with high resolution across curves, bends and twists at varying thicknesses.
Further work will concentrate on the refinement of both the proprietary material and array manufacture process to improve the signal output and array sensitivity.
