The fracture toughnesses of some precipitation-hardened aluminum alloys have been evaluated, mainly by the use of precracked three-point bend specimens in instrumented impact testing. A recently developed interpretation of the specific surface energy method has been applied to calculate the initiation values of the critical value of stress intensity factor K sub Ic) and these values have been compared with those calculated using stress analysis equations. The value of unity thereby deduced for the geometrical constraint factor in these non-rate-sensitive materials may be appropriate of the type of fracture mode occurring in these alloys, that is, semiductile. The distinction in principle between fracture initiation toughness, expressed as G sub Ic equals w/eta A, and the average propagation toughness W/A has been noted and the latter used in studying crack tunnelling during semiductile crack propagation in thick sections of the sections of the alloys in the form of large, double-cantilever beam specimens. /AUTHOR/

  • Corporate Authors:

    American Society for Testing and Materials

    100 Barr Harbor Drive, P.O. Box C700
    West Conshohocken, PA  United States  19428-2957
  • Authors:
    • Johnson, F A
    • Radon, J C
  • Publication Date: 0

Media Info

Subject/Index Terms

Filing Info

  • Accession Number: 00126509
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Jan 14 1976 12:00AM