Fracture mechanics toughness tests - Part 3.Method for determination of fracture toughness of metallic materials at rates of increase in stress intensity factor greater than 3.0 MPa m0.5 s-1
This part of BS 7448 describes a method for determining the opening mode plane strain fracture toughness
KIc, the critical crack tip opening displacement (CTOD) fracture toughness and the critical J fracture
toughness of metallic materials. The method uses fatigue precracked specimens tested in displacement
control at rates of increase in stress intensity factor greater than 3.0 MPa·ms but less than
3 000 MPa·ms during the initial elastic deformation. Stress intensity factors greater than
3 000 MPa·ms are covered in Annex A. These rates are greater than those permitted in BS 7448-1.
The definition of fracture toughness values relevant to particular structural integrity assessments is outside the scope of this British Standard.
NOTE This standard does not cover integrity assessments. Such assessments are covered in BS 7910.
note:1) 1 N.mm = 0.0316 MPa·m = 0.0316 MN·m.