EFFECT OF GRAIN SIZE AND CARBON CONTENT ON THE LOW TEMPERATURE TENSILE PROPERTIES OF HIGH PURITY FE-C ALLOYS

Several low carbon ferrites, approximately 99.9+% pure apart from added carbon and substantially free of oxygen, nitrogen and hydrogen, were prepared and tested in tension under various conditions of heat treatment, ferrite grain size, and test temperature. True stress-strain curves were calculated and the significant tensile parameters evaluated. Ferrite grain size was shown to be the sole factor determining ductility of 0.02% carbon alloys at liquid air temperature; decreasing the grain size causes a remarkable increase in ductility. With more than 0.02% carbon, carbide morphology has an important effect on the ductility. Heat treatments which resulted in carbides at the grain boundaries materially reduced the low temperature ductility. The exponent of strain hardening was found to decrease with decreasing temperature, increasing carbon content, and increasing grain size. The initial presence of a substructure or a decrease in grain size markedly increased the yield stress at liquid air temperatures. Twinning was not found to contribute to the low temperature brittleness.

  • Corporate Authors:

    University of Pennsylvania Law School

    3400 Chestnut Street
    Philadelphia, PA  United States  19104

    Ship Structure Committee

    National Academy of Science, 2101 Constitution Avenue, NW
    Washington, DC  United States  20418
  • Authors:
    • Smith, R L
    • Spangler, G
    • Brick, R M
  • Publication Date: 1954-5-28

Media Info

  • Features: References;
  • Pagination: n.p.

Subject/Index Terms

Filing Info

  • Accession Number: 00331284
  • Record Type: Publication
  • Source Agency: Ship Structure Committee
  • Report/Paper Numbers: SSC- 81 Prog Rpt.
  • Contract Numbers: NObs-50062
  • Files: TRIS
  • Created Date: May 21 1981 12:00AM