Business from technology

Usability and failure mechanisms of materials

Competence

Managing the usability and ageing of structures and components throughout a power or process plant’s service life requires identification and evaluation of the degradation mechanisms of structural materials in actual service environments. VTT’s competence in this area includes::

• Comprehensive understanding of the relationships between material microstructure, external loading and environmental factors leading to corrosion and degradation phenomena.
  
• Innovative techniques for experimental investigations and modelling of material damage and failure mechanisms under controlled conditions of temperature, pressure and radiation in gaseous and liquid environments (actual or simulated).
  
• Experimental and modelling capabilities regarding fracture mechanics of single and multi component materials and interfaces, including the “Master Curve” approach.
  

Challenges

Safe and reliable use and life extension of power and process plants by:

• identifying and verifying failure mechanisms under aggressive conditions.
  
• contributing to proactive degradation assessments for plant lifetime management, plant life extensions and power upgrades.
  
• supporting licensing of nuclear components, such as reactor pressure vessels.
  

Solutions

• Experimental platforms for
  
  • Mechanical and fracture testing
    
  • Mechanical testing in simulated coolant environments
    
  • Mechanical testing of activated materials
    
  • Exposure testing in hot gas environment
    
  • Water chemistry and electrochemical corrosion research
    
  • Materials characterisation
    

• Participation in national and international programmes and networks: SAFIR2010, KYT2010, EU-PERFORM60, EU-MTR-I3, EU-ANTIOXI, OECD Halden reactor project, IAEA FUWAC.
  
• Handling and mechanical testing of activated materials in Hot-Cells.
  
• Development of mechanical, corrosion and electrochemical research devices for challenging conditions.
  
• Modelling of degradation phenomena (creep, fracture) and interaction between material and environment (oxidation, activity build-up, localised corrosion).
  

Benefits

• Assure safe and economic operation of power and process plants
  
• Contribute to plant life extension and power upgrade assessments
  
• Collate knowledge and experience through participation in national and international programmes and networks.
  

References and merits

• VTT’s Master Curve base for international FM standards and SI assessment procedures (ASTM E1921, ASME N-629/631, BS 7910, EN 13445-2 etc.).
  
• VTT experts take actively part in numerous international networks and working groups.
  
• VTT co-ordinates the large EU NULIFE Network on plant life management.