STP514

    Fracture Toughness of Duplex Structures: Part II — Laminates in the Divider Orientation

    Published: Jan 1972


      Format Pages Price  
    PDF (436K) 16 $25   ADD TO CART
    Complete Source PDF (4.1M) 16 $61   ADD TO CART


    Abstract

    Laminates containing 25 percent of tough (unaged) maraging steel plates and 75 percent of brittle (aged) maraging steel plates were prepared by a special diffusion bonding and heat treating technique so that the thickness of the tough constituent was either 0.02, 0.04, 0.06, or 0.08 in. Compact tension fracture toughness specimens were machined so that the laminates were parallel to the sides of the specimens. They were then fractured according to the recommendations of the ASTM and three indices of toughness were measured: KIc, as recommended by the ASTM, Komax based on the maximum load and original crack length and Kimax, based on the maximum load and instantaneous crack length. Four tests were performed at each thickness of the tough constituent; two each at crack lengths of approximately 0.30 and 0.55 in. The plane-strain fracture toughness of the laminates was slightly higher than KIc of the monolithic brittle constituent and was independent of either crack length or the dimensions of the tough constituent. Regardless of the thickness of the tough phase the composite toughness was highest for specimens containing cracks 0.30 in. long when the throughness was measured in terms of Komax or Kimax. The thoughnessas a function of thickness exhibited a relative maximum when the tough phase was 0.04 in. thick and a relative minimum when the tough phase was 0.06 in. thick for both the 0-30 and 0.55-in. crack lengths. The experimental results are in broad agreement with a proposed model for crack extension in the divider orientation.

    Keywords:

    fracture strength, toughness, fracture (materials), maraging steels, laminates, metals, fractography, analytic geometries


    Author Information:

    Antolovich, SD
    University of Cincinnati, Cincinnati, Ohio

    Kasi, K
    University of Cincinnati, Cincinnati, Ohio

    Chanani, GR
    University of Cincinnati, Cincinnati, Ohio


    Paper ID: STP38823S

    Committee/Subcommittee: E08.08

    DOI: 10.1520/STP38823S


    CrossRef ASTM International is a member of CrossRef.