DYNAMIC INITIATION OF BRITTLE FRACTURE IN STATICALLY LOADED MILD STEEL WELDED STRUCTURES

Dynamic fracture mechanics can be used not only for impact loading but also for static (slow) loading. Dynamic initiation can occur in slow loading when an embrittled area cracks, either by direct propagation into surrounding material or by a latter initiation from a part of the crack, still situated in the embrittled area. The tip of a sharp flaw can be embrittled after its occurrence by thermal strain ageing by later weld passes. The basic probabilistic fracture mechanics approach is introduced and the probable occurrence of embrittled zones and external impact loadings are discussed in examples also involving fatigue loading and different consequences of a fracture. In a special investigation, a crack in a probably embrittled zone could be allowed to remain in the structure if dynamic fracture toughness data prove the arresting capability of the parent material in the as-welded state, and of all zones in a welded joint in a stress-relieved or high heat input welded structure. The dynamic approach makes fracture mechanics applicable in practical situations involving narrow zones and cracking.

Media Info

  • Features: References;
  • Pagination: p. 21-29

Subject/Index Terms

Filing Info

  • Accession Number: 00164413
  • Record Type: Publication
  • Source Agency: Engineering Index
  • Report/Paper Numbers: Paper 2 Conf Paper
  • Files: TRIS
  • Created Date: Nov 9 1977 12:00AM