Barkhausen noise analysis plays a role in aviation safety

Preventing Failures in Ground Steel Parts.

RoboScan measuring a hypoid

In September 2018, Flight Global reported on an incident that occurred on a commercial aircraft in which an axle fatigue crack led to a failure of the left nose landing gear axle and separation of the left nose wheel.

“Air Accidents Investigation Branch (AAIB) analysis found that the axle journal, while being overhauled, had sustained a re-tempering burn during post-chrome plate grinding.”

The AAIB investigated the issue and concluded that:

“The cause of the abusive grinding could not be determined, but the abusive grinding would probably have been identified if a post-grinding Barkhausen inspection had been carried out.”

“If a Barkhausen inspection had been carried out on EI-DLV’s NLG at the beginning of the overhaul process then there would have been no need to strip the chrome, re-plate and grind the journals, thus removing the opportunity for abusive grinding to occur.”

Barkhausen noise analysis is a non-destructive testing method involving the measurement of a noise like signal induced in a ferromagnetic material by an applied magnetic field.

See the video for example of robotic Barkhausen noise measurement: