You are being redirected because this document is part of your ASTM Compass® subscription.
    This document is part of your ASTM Compass® subscription.

    If you are an ASTM Compass Subscriber and this document is part of your subscription, you can access it for free at ASTM Compass
    STP1329

    Developing Fracture Assessment Methods for Fusion Reactor Materials with Small Specimens

    Published: 01 January 1998


      Format Pages Price  
    PDF (752K) 30 $25   ADD TO CART
    Complete Source PDF (12M) 624 $162   ADD TO CART

    Cite this document

    X Add email address send
    X
      .RIS For RefWorks, EndNote, ProCite, Reference Manager, Zoteo, and many others.   .DOCX For Microsoft Word


    Abstract

    Design and operation of fusion reactors will require a temperature-dependent effective toughness [Ke(T)] data base. Effective toughness is a function of intrinsic metallurgical/microstructural factors, degraded by irradiation, and extrinsic factors, such as size and geometry. Standard fracture mechanics is inadequate, since the presumption of geometrically independent crack tip stress/strain fields does not apply to either small specimens or in thin-walled structures with shallow cracks. More general approaches to measuring and applying Ke(T) data are described for cleavage initiation in steels and vanadium alloys. The critical stress-critical area (σ*/A*) mechanism of cleavage initiation is demonstrated using a confocal microscopy/fracture reconstruction method that can also directly measure Ke. The σ*/A* model is combined with finite element method (FEM) simulations of crack tip fields to: a) predict Ke(T) for F-82H as a function of size; and b) directly adjust Ke(T) data to a common test geometry. A simpler master curve-(temperature) shift method is also described. Changes in yield stress due to irradiation or strain rates can be related to the shifts. Indeed, tensile properties as a function of temperature, strain rate and alloy condition are required by all assessment methods. Physically-based small specimen methods will reduce enormously what would otherwise be a prohibitive amount of testing.

    Keywords:

    fusion materials, fracture, confocal microscopy, fracture reconstruction, fracture toughness, micromechanics


    Author Information:

    Odette, GR
    Professor, University of California Santa Barbara, CA

    Edsinger, K
    Graduate Student or Former Graduate Student, University of California Santa Barbara, CA

    Lucas, GE
    Professor, University of California Santa Barbara, CA

    Donahue, E
    Graduate Student or Former Graduate Student, University of California Santa Barbara, CA


    Committee/Subcommittee: E10.02

    DOI: 10.1520/STP37997S