1st European Mechanics of Materials Conference on Local Approach to Fracture '86 - 96'
J. Phys. IV France 06 (1996) C6-295-C6-304
The Effect of Temperature and Specimen Geometry on the Parameters of the "Local Approach" to Cleavage FractureC.S. Wiesner and M.R. Goldthorpe
TWI, Abington Hall, Abington, Cambridge CBl 6AL, U.K.
The present work investigates the temperature and specimen geometry dependence of the Weibull parameters of a structural steel (BS 4360 Grade 50D). Notched tensile, notched (Charpy-type) four point bend and fracture mechanics specimens have been used to study the effect of specimen geometry. Axisymmetric and two and three-dimensional finite element analyses have been carried out to determine Weibull parameters for the three specimen types at various temperatures. The results have shown that the parameters determined using notched tensile specimens can be regarded as temperature independent. However, the parameters determined using notched bend and fracture mechanics specimens exhibited some dependence on temperature. There were also differences between the Weibull parameters determined from the different specimen geometries. The results show that there is a need to further develop the 'Local Approach' to cleavage fracture to incorporate effects of temperature and plastic constraint. At present, it is recommended that fracture mechanics specimens be used for the determination of Weibull parameters if the results are to be applied to cracked structures.
© EDP Sciences 1996