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Monitoring Hydrogen Embrittlement with Acoustic Emission Testing

Project Code: 34243

Start date and planned duration: February 2021, 30 months


  • Design an appropriate hydrogen embrittlement (HE) test that allows acoustic emission (AE) analysis of the damage mechanism.
  • To evaluate the capability of AE in detecting and locating hydrogen embrittlement in controlled laboratory conditions.
  • To establish the accuracy of AE monitoring in assessing the hydrogen embrittlement damage mechanism using other non-destructive teating techniques as validation tools.
  • To evaluate the capability of AE in detecting the stage of the damage and to discriminate AE signals generated from diverse sources of noise from the actual damage mechanism present under each stage.

Project Outline

To support a transition to greater use of hydrogen as an energy resource, steel pipelines and onshore refineries are being converted to handle 100% hydrogen fluids. High-strength steel alloys are, however, susceptible to various damage mechanisms associated with hydrogen, including hydrogen embrittlement (HE). This is caused by the presence of excess hydrogen and is expected to be a significant factor in the drive towards the hydrogen economy, in addition to its current importance related to the use of cathodic protection in marine environments. A non-destructive testing (NDT) technique to detect the early stages of crack initiation related to HE would be of significant benefit, both to the research community and to owners and operators of infrastructure.

Continuous monitoring of structures and machinery is now routine in many industries. Acoustic emission (AE) testing is an established NDT method for detecting crack initiation in metals under tensile and fatigue load. The dislocations created during plasticisation of a notch under load before the crack appears are known to create measurable AE bursts of stress waves, so called AE ‘hits’. The challenge is to detect these in the presence of background AE noise. Previous experience in developing novel AE signal analysis methods that distinguish signals from noise and artefacts will be exploited in this project to develop AE testing for the detection and monitoring of HE on susceptible materials and structures.


Industry Sectors

Oil and Gas



Benefits to Industry

Increased confidence in the behaviour of materials in hydrogen environments, facilitating the transition to a hydrogen economy.

Detection of the early stages of hydrogen embrittlement without the requirement for destructive testing.


 Research Board Portal 

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