- since 1996 -
|NDT.net Issue - 2014-06 - NEWS ||NDT.net Issue: 2014-06|
Publication: e-Journal of Nondestructive Testing (NDT) ISSN 1435-4934 (NDT.net Journal)
TWI successfully completes development of two automated digital X-ray radiography inspection systems for different applicationsTWI Ltd (The Welding Institute)193, Great Abington, Cambridge, United Kingdom
Digital radiography (DR) allows the volumetric inspection of the part under inspection and usually reveals more information about a part than any other inspection technique. Just over two years ago Dr Mihai Iovea of Accent Pro 2000 s.r.l., and co-ordinator of two European-funded consortiums AutoInspect and PlastronicsSpec, invited TWI Technology Centre (Wales) to become involved in the radiography development of two completely different inspection applications aimed at different industry sectors.
The AutoInspect system has been developed for the inspection of powder metallurgy (PM) parts, while the PlastronicsSpec system has been developed for the plastic electronics market.
In the PM industry, PM parts can suffer from porosity and cracking; hence the need for an automated inspection to ensure 100% quality of parts. The use of digital X-ray radiography allows parts to be inspected without being destructed.
The AutoInspect consortium has developed a digital radiographic system for the online inspection of sintered powder metallurgy and metal injection moulded parts.
The main features of the AutoInspect system are:
This technique has been developed to detect small cracks, flaws and density variations in-line during the manufacturing process of PM parts produced in a factory environment.
For the plastic electronics industry, organic light emitting diodes (OLEDs) used in digital displays need to be checked for quality. Specifically, the end user in the PlastronicsSpec consortium produced OLEDs by inkjet printing. This OLED inkjet printing process can result in defective pixels, resulting from cracks, chips, pin holes and misaligned layers. The objective of the developed PlastronicsSpec system is to perform rapid and high resolution inspection of printed plastic flat panels or reel-to-reel flexible electronics sheet using real-time digital radiographic imaging. This enables the automatic detection and instant rejection of defective products with minimum wastage and the elimination of human error in data interpretation.
The main features of the PlastronicsSpec system are:
TWI Technology Centre (Wales) developed, optimised and automated the digital X-ray inspection based techniques for both projects. TWI first simulated the radiography environment to optimise the placement of the X-ray source and detector, surveyed the market for the appropriate source and detector, and finally procured the most suitable X-ray source and detectors for the intended applications.
The two applications could not be more different in terms of radiography. For the PM samples the team identified high energy (160-200kV) to penetrate the material, whereas for the OLED inspection the energies had to be low (55kV) to avoid being destructive to the OLED panels. For the PM parts the goal was to inspect defects such as cracking to 25μm resolution, whereas with OLED display inspection the requirement was to resolve flaws down to 2-4μm.
Project co-ordinator Dr Mihai Iovea thanks TWI and states that, because of the contribution of TWI and other collaborators, he is in a very good position to commercially exploit the completed prototypes.
TWI can develop one-off automated inspection prototypes and solutions for its Members. If you think you might have an inspection requirement where digital radiography can be deployed, or you need to inspect a component using radiography, please contact firstname.lastname@example.org.
More information about the projects can be found at www.autoinspectproject.eu and www.plastronicsspec.eu
The PlastronicsSpec project has received funding from the European Union under grant agreement no. 286531. The AutoInspect project received funding from the European Union under grant agreement no. 286007.