By the 3rd volume the abstracts were arranged under the order in which the papers had been read at the meetings the report of each discussion meeting was headed by a brief account of the business which preceded the reading of the papers. The effect of residual stresses on the initiation of ductile fracture has also been demonstrated.Ī meeting of the Council on May 10th, 1832 resolved that abstracts of papers submitted for publication in the Philosophical Transactions from the year 1800 be published in Proceedings. Cleavage fracture toughness levels of the less constrained centre-cracked wide plates may be reduced to below the toughness levels of the highly constrained bend specimen because of residual stress effects. It has been shown that the concept of the T-stress is not readily applicable in the presence of residual stresses unless primary and secondary stresses are treated separately.
Results of full-field three-dimensional finite-element analyses for stresses at the crack tip have been discussed in relation to the two-dimensional T-stress analysis. A biaxial residual stress state can increase constraint effectively even in the case of the longitudinal stress component parallel to the crack flank being compressive.
It has been found that tensile longitudinal residual stresses parallel to the crack flank increase constraint while compressive stresses in this direction have the opposite effect. Three-dimensional finite-element analyses, including the effects of large elastic-plastic deformation, have been conducted on centre-cracked plates subjected to various residual stress fields and transverse externally applied loads. Investigations have been carried out into the effects of residual stresses on constraint and on fracture behaviour by means of finite-element analyses and local fracture criteria. By the very nature of their origin through shrinkage effects, residual stress states can be expected to be triaxial in large structures.