Sunday 7 September 2008
HIGH-TEMPERATURE LOW CYCLE FATIGUE AND THERMOMECHANICAL FATIGUE. PRACTICAL PROCEDURES TO VALIDATE THE START-UP OF NEW TESTING SYSTEM IN ANSALDO ENERGIA
E. Poggio1, S. Budano2
1 Ansaldo Energia (AEN) S.p.A Via Nicola Lorenzi 8, 16152 Genoa, Italy
2 Centro Sviluppo Materiali (CSM) S.p.A. Via di Castel Romano 100, 00128 Rome, Italy
Referee: M.Barteri; V. Ratto
Paper presented to LCF6 6th Intern. Conf. on Low Cycle Fatigue September 7-12, 2008,
Berlin, Germany
ABSTRACT
A fine procedure for LCF and TMF has been defined according to the available ASTM standards and EU recommendation to start-up a new generation of MTS testing system. The results obtained from specimens extracted from steel and nickel based super-alloy selected for power plant generation components call to rearrange the heating coil changing the material in order to optimize thermal gradient. Fracture analysis to individuate single or better multiple crack initiation sites around the surface of the specimens gives good support to validate the alignment of the load axis. LCF isothermal tests are validated by a cross correlation to TMF tests carried out at the same range of temperatures and strains
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