CRITICAL STRESSES FOR SLIP, TWINNING, AND CLEAVAGE IN SINGLE CRYSTALS OF IRON

An X-Ray, optical and metallographic study of the stresses for--and mechanisms of--slip, twinning and fracture in single crystals of iron prepared from decarburized mild steel has been made. The selection of the glide ellipse has been found to be a function of the relative difficulty of atom motions at various positions along a (111); this function being affected by temperature and distribution of stress. A critical shear stress criterion applies. Twinning has been found to occur on (112) type planes and in (111) directions below -170 deg C. as predicted by a critical shear stress law, mutatis mutandis. The twinning stress is greatly affected by slip. Brittle fracture could be accounted for by a critical normal stress theory within wide limits of error. Ductile fractures predominated for specimens where a cleavage plane, (001), was more than 65 degrees axis. Various effects of prestraining were observed.

  • Corporate Authors:

    Carnegie Mellon University

    Wean Hall 4323
    5000 Forbes Avenue
    Pittsburgh, PA  USA  15213-3890

    Ship Structure Committee

    National Academy of Science, 2101 Constitution Avenue, NW
    Washington, DC  USA  20418
  • Authors:
    • Cox Jr, J J
  • Publication Date: 1954-2-1

Media Info

  • Features: References;
  • Pagination: 141 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00331009
  • Record Type: Publication
  • Source Agency: Ship Structure Committee
  • Report/Paper Numbers: SSC- 66 Final Rpt.
  • Contract Numbers: NObs-50230
  • Files: TRIS
  • Created Date: May 21 1981 12:00AM