New testing technique could speed up metal additive manufacturing in aerospace

The technique, which uses laser ultrasound to detect defects, is being developed by Dr Ben Dutton from the Manufacturing Technology Centre in Coventry, UK.

His work could encourage the use of additive manufacturing within mass manufacturing industries as it removes the need for a separate inspection process once components are built. It also responds to the need for new and improved testing techniques in view of the increased use of additive manufacturing in industries such as automotive and aerospace. This work will be revealed at the NDT 2017 conference in Telford, UK on 6 September.

Dutton, an expert in non-destructive testing, said: “Currently some additive manufacturing systems incorporate in-process monitoring but they use cameras to take snapshots of the layers as the item is being created. The problem with cameras is that each new layer of powder can conceal part of the defect. With NDT methods such as laser ultrasound, there is a certain amount of penetration so you can look below the top layer and detect sub-surface defects in a non-contact way.”

The technique has shown potential for use with powder bed and directly deposited additive manufacturing processes, and with components of complex shape.

Dutton is also playing a key role in the development of new ISO standards for inspecting additive manufactured components.

He continued: “Inspecting components during the build process will reduce waste. If you spot a defect you consider unacceptable, you can try to stop the build straight away without having to waste the full part. It would also improve efficiency as, ideally, it would remove the need for a separate inspection once the build is complete. In terms of using additive manufacturing within mass manufacturing, in-process inspection is the future.”

Find our more at a series of talks on inspecting additive manufactured parts on Wednesday 6 September at NDT 2017, the conference of the British Institute of Non-Destructive Testing, which runs alongside the Materials Testing 2017 exhibition. Both events take place at the International Centre, Telford from 5-7 September.

www.bindt.org/events/ndt-2017

www.materialstesting.org