THERMAL SCIENCE

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Thermal Science - Online First

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Creep crack growth behavior of P91 steel weldments

ABSTRACT
The steels operating at elevated temperatures are well known to be exposed to premature failure due to cracking caused by constant thermal stress, i.e. secondary creep process. Therefore, creep crack growth (CCG) tests were carried out on compact tension (CT) specimens machined from P91 weld joint at 600°C to determine its behaviour in realistic conditions. At the same time, numerical method for predicting the CCG in CT specimens by a series of incremental steady state finite element (FE) analysis were performed using Norton's law to represent creep behaviour. Verification of the FE predictions were obtained for weld metal (WM) and heat affected zone (HAZ) by comparison with experimental results, indicating at the same time that creep crack growth rates are significantly higher for WM than for BM.
KEYWORDS
PAPER SUBMITTED: 2017-07-29
PAPER REVISED: 2017-11-15
PAPER ACCEPTED: 2017-11-17
PUBLISHED ONLINE: 2017-12-03
DOI REFERENCE: https://doi.org/10.2298/TSCI170729240S
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