Calculated shoulder to gauge ratio of fatigue specimens in PWR environment

A ratio of Shoulder to Gauge displacements (S2G) is calculated for three different fatigue specimens in pressurized water environment. This ratio needs to be known beforehand to determine the applied shoulder displacements during the experiment that would result in the desired strain amplitude in the gauge section. Significant impact of both the applied constitutive law and specimen geometry on the S2G is observed. The calculation using the fully elastic constitutive law results in the highest S2G values and compares very well with the analytical values. However, this approach disregards the plastic deformation within the specimens which mostly develops in the gauge section. The results with the constitutive law based on the JACOBS and INCEFA N25/2 fatigue curves are more representative and result lower S2G values compared to the ones obtained with the fully elastic constitutive law. Calculating S2G values using elastic-plastic constitutive law based on the monotonic uniaxial tensile test should be avoided as they are significantly lower compared to the ones computed with elastic-plastic laws derived from hysteresis loops at half-life, N25/2.

SIMONOVSKI Igor;  MCLENNAN Alec;  MOTTERSHEAD Kevin;  GILL Peter;  PLATTS Norman;  BRUCHHAUSEN Matthias;  WATERS Joshua L.;  VANKEERBERGHEN Marc;  MORENO Germán Barrera;  ARRIETA GOMEZ Sergio;  NOVOTNY Radek; 

2021-03-02

MDPI

JRC122153

2075-4701 (online),   

https://doi.org/10.3390/met11030376,    https://publications.jrc.ec.europa.eu/repository/handle/JRC122153,   

10.3390/met11030376 (online),