Duration: November 2014 – September 2018.

People:

  • Researcher: Eimear O’Hara (PhD Student).
  • Supervisors: Dr. Richard Barrett, Prof. Sean Leen.
  • Academic Collaborators: Prof. Noel O’Dowd, Director MSSI, University of Limerick; Prof. Dongfeng Li, Harbin Institute of Technology of Shenzhen Graduate School, Shenzhen, China; Dr. Richard Barrett, Dr. Noel Harrison.
  • Technical Team: Mr. Bonaventure Kennedy, Mr. Pat Kelly.
  • Industrial Partners: Alstom Power Ltd., Doosan-Babcock, ESB Energy International.
  • Funding Source: College of Engineering & Informatics Scholarship.

Summary:

The aim of this research is to characterise the multi-scale thermo-mechanical performance of advanced next generation power plant materials and develop a novel multi-scale modelling methodology for advanced 9Cr steels under a range of loading conditions. A program of experimental testing, including high temperature low cycle fatigue, creep and corrosion-fatigue testing, will allow material characterisation and validation of material models. These models will include continuum damage mechanics, to predict component life-time, and multi-scale dislocation-mechanics, incorporating key strengthening and deformation mechanisms via primary microstructural variables.

Publications:

Barrett, R. A., O’Hara, E., O’Donoghue, P. E., Leen, S. B. “High Temperature Low Cycle Fatigue Behaviour of MarBN at 600 °C.” Accepted to ASME Journal of Pressure Vessel Technology, 2015.

Barrett, R. A., O’Hara, E., O’Donoghue, P. E., Leen, S. B. “High Temperature Low Cycle Fatigue Characterisation of MarBN at 600 °C.” ASME Pressure Vessels & Piping Conference, Boston, July 19th to 23rd, 2015.

Images:

Figure 1. INSTRON 8800 high temperature low cycle fatigue test rig at NUI Galway.

Strain-rate modelling of MarBN at 600 °C.
Strain-range modelling of MarBN at 600 °C.

Figure 2. Strain-rate modelling of MarBN at 600 °C.

Figure 3. Strain-range modelling of MarBN at 600 °C.

SEM image of inclusions and fatigue striations on the MarBN fracture surface.
SEM image of inclusions and fatigue striations on the MarBN fracture surface.

Figure 4. SEM image of inclusions and fatigue striations on the MarBN fracture surface.

Figure 5. SEM image of dimple rupture on the MarBN fracture surface.