An engineering methodology for constraint corrections of elastic–plastic fracture toughness – Part II: Effects of specimen geometry and plastic strain on cleavage fracture predictions

Abstract This work extends a micromechanics model for cleavage fracture incorporating effects of plastic strain to determine the reference temperature, T 0 , for an A515 Gr 65 pressure vessel steel based on a modified Weibull stress ( σ w ) . Non-linear finite element analyses for 3-D models of plane-sided SE(B) and PCVN specimens define the relationship between σ w and J from which the variation of fracture toughness across different crack configurations is predicted. The modified Weibull stress methodology yields estimates of T 0 from small fracture specimens which are in good agreement with the corresponding estimates derived from testing of larger crack configurations.

[1]  Martin Kroon,et al.  A probabilistic model for cleavage fracture with a length scale-influence of material parameters and constraint , 2002 .

[2]  Robert H. Dodds,et al.  Constraint effects on the ductile-to-brittle transition temperature of ferritic steels: a Weibull stress model , 2000 .

[3]  Robert H. Dodds,et al.  Numerical investigation of 3-D constraint effects on brittle fracture in SE(B) and C(T) specimens , 1996 .

[4]  Robert H. Dodds,et al.  Calibration of the Weibull stress scale parameter, σu, using the Master Curve , 2004 .

[5]  A. Pineau,et al.  A local criterion for cleavage fracture of a nuclear pressure vessel steel , 1983 .

[6]  Maurice G. Kendall,et al.  The advanced theory of statistics , 1945 .

[7]  Tirumalai S. Srivatsan,et al.  Prediction of Cleavage Fracture in Ferritic Steels: A Modified Weibull Stress Model , 2005 .

[8]  A. J. McEvily,et al.  Fracture of Structural Materials , 1967 .

[9]  Claudio Ruggieri,et al.  Transferability of elastic–plastic fracture toughness using the Weibull stress approach: significance of parameter calibration , 2000 .

[10]  Claudio Ruggieri,et al.  Calibration of Weibull stress parameters using fracture toughness data , 1998 .

[11]  Takuya Yamamoto,et al.  Influence of statistical and constraint loss size effects on cleavage fracture toughness in the transition—A single variable experiment and database , 2006 .

[12]  D. Munz,et al.  Estimation procedure for the Weibull parameters used in the local approach , 1992, International Journal of Fracture.

[13]  Kim Wallin,et al.  The scatter in KIC-results , 1984 .

[14]  C. Shih,et al.  Family of crack-tip fields characterized by a triaxiality parameter—II. Fracture applications , 1992 .

[15]  A. Pineau,et al.  Development of the Local Approach to Fracture over the Past 25 years: Theory and Applications , 2006 .

[16]  Kim Wallin,et al.  Fracture of brittle particles in a ductile matrix , 1986 .

[17]  Kim Wallin,et al.  Applicability of miniature size bend specimens to determine the master curve reference temperature T0 , 2001 .

[18]  Gao,et al.  A Weibull stress model to predict cleavage fracture in plates containing surface cracks , 1999 .

[19]  Robert H. Dodds,et al.  Coupling of the Weibull stress model and macroscale models to predict cleavage fracture , 2004 .

[20]  Robert H. Dodds,et al.  Temperature dependence of Weibull stress parameters: Studies using the Euro-material , 2006 .

[21]  K. Wallin,et al.  Irradiation damage effects on the fracture toughness transition curve shape for reactor pressure vessel steels , 1993 .

[22]  F. M. Burdekin,et al.  Engineering critical analyses to BS 7910 — the UK guide on methods for assessing the acceptability of flaws in metallic structures , 2000 .

[23]  B. J. Brindley,et al.  The effect of dynamic strain-ageing on the ductile fracture process in mild steel , 1970 .

[24]  N. Singpurwalla,et al.  Methods for Statistical Analysis of Reliability and Life Data. , 1975 .

[25]  D. M. Knowles,et al.  A new statistical local criterion for cleavage fracture in steel. Part I: model presentation , 2004 .

[26]  Mark T. EricksonKirk,et al.  Insights and Observations Arising From Curve-Fitting the Charpy V-Notch and Tensile Data Contained Within the United States’ Light Water Reactor Surveillance Database , 2008 .

[27]  R. H. Dodds,et al.  An engineering methodology for constraint corrections of elastic–plastic fracture toughness – Part I: A review on probabilistic models and exploration of plastic strain effects , 2015 .

[28]  Robert H. Dodds,et al.  Continuum and micromechanics treatment of constraint in fracture , 1993, International Journal of Fracture.

[29]  James A. Joyce,et al.  Development of the T0 reference temperature from precracked Charpy specimens , 2001 .

[30]  Claudio Ruggieri,et al.  An engineering methodology to assess effects of weld strength mismatch on cleavage fracture toughness using the Weibull stress approach , 2010 .

[31]  K. Wallin,et al.  Fracture Toughness Transition Curve Shape for Ferritic Structural Steels , 1991 .

[32]  C. E. Richards,et al.  A critical of carbide cracking mechanisms in ferride/carbide aggregates , 1970 .

[33]  Claudio Ruggieri,et al.  A Weibull Stress Approach Incorporating the Coupling Effect of Constraint and Plastic Strain in Cleavage Fracture Toughness Predictions , 2014 .

[34]  J. Gurland,et al.  Observations on the fracture of cementite particles in a spheroidized 1.05% c steel deformed at room temperature , 1972 .

[35]  G. T. Hahn,et al.  The Influence of Microstructure on Brittle Fracture Toughness , 1984 .

[36]  B. Moran,et al.  A general treatment of crack tip contour integrals , 1987 .

[37]  Kim Wallin,et al.  Master curve analysis of the Euro fracture toughness dataset , 2002 .

[38]  F. Mudry,et al.  A local approach to cleavage fracture , 1987 .

[39]  C. Shih,et al.  Family of crack-tip fields characterized by a triaxiality parameter—I. Structure of fields , 1991 .

[40]  Claudio Ruggieri,et al.  Influence of threshold parameters on cleavage fracture predictions using the Weibull stress model , 2001 .

[41]  Anssi Laukkanen,et al.  New developments of the Wallin, Saario, Törrönen cleavage fracture model , 2008 .

[42]  Claudio Ruggieri,et al.  A transferability model for brittle fracture including constraint and ductile tearing effects: a probabilistic approach , 1996 .

[43]  Kim Wallin,et al.  An Introduction to the Development and Use of the Master Curve Method , 2005 .