STP1172

    Some Observations in Fracture Toughness and Fatigue Testing with Chevron-Notched Specimens

    Published: Jan 1992


      Format Pages Price  
    PDF Version (436K) 17 $25   ADD TO CART
    Complete Source PDF (4.9M) 17 $75   ADD TO CART


    Abstract

    Chevron-notched specimens were used to test metallic and ceramic materials over a range of temperatures and testing conditions. The materials tested were M-50 bearing steel, alumina, silicon carbide, monolithic silicon nitride, and in situ toughened silicon nitride. Results were compared to measurements performed with compact-tension specimens, singleedge notched beam specimens, or single-edge precracked beam specimens.

    Measured properties included fracture toughness, crack growth resistance, and fatigue crack growth rate. For materials with rising R-curves, the fracture toughness measured with chevron-notched specimens was dependent on specimen proportions and notch geometry, as related to the amount of crack extension to the measurement point. For materials with flat R-curves, the chevron-notch test is independent of notch geometry and specimen proportions.

    Keywords:

    silicon nitride, silicon carbide, alumina, bearing steel, crack growth resistance, fracture toughness, chevron notch, fatigue crack growth


    Author Information:

    Salem, JA
    National Aeronautics and Space Administration, Lewis Research Center, Cleveland, OH

    Shannon, JL
    National Aeronautics and Space Administration, Lewis Research Center, Cleveland, OH

    Jenkins, MG
    Oak Ridge National Laboratory, Oak Ridge, TN


    Paper ID: STP24707S

    Committee/Subcommittee: E08.04

    DOI: 10.1520/STP24707S


    CrossRef ASTM International is a member of CrossRef.