Constraint Correction in Prediction of Refrence Temperature(t0)from Three Point Bending Specimen of Different Thickness by Weibull Stress (for RPV Material, 20mnmoni55 Steel)
Refrence temperature (T0) of 20MnMoNi55steel is calculated, in accordance with ASTM E-1921 for different
thickness of Three Point Bending Specimen.Difference in thickness causes variation in constraint label which deviates from
Small Scale Yielding (SSY) condition causing a non-conservative prediction of T0.In this study Finite Element Analysis is
used to calculate Weibull Stress verses J-Integral plot with increase in loading label, for each thickness of the specimen and
its respective SSY model.Experimental KJC value,for different thickness is corrected with its equivalent SSY model from the
Weibull Stress verses J-Integral plot.The Corrected T0 values reflects too much over prediction of Refrence temperature T0
from E-1921due to deviation of SSY condition.
Keywords - Weibull Stress,Small Scale Yielding, Reference Temperature(T0),Fracture Toughness,Constraint.