STP1072

    Significance of Precracking Variables for Slow-Bend Charpy Tests

    Published: Jan 1990


      Format Pages Price  
    PDF Version (532K) 34 $25   ADD TO CART
    Complete Source PDF (3.8M) 34 $55   ADD TO CART


    Abstract

    The significance of four variables in the technique used to precrack Charpy specimens of metallic materials is determined by analyses of seven responses computed from results of slow-bend tests. The variables include crack size, stress-intensity factor at the start of precracking, notch preparation prior to precracking, and material. All four variables are shown here to be significant for more than one of the computed responses. Seven response parameters, each representing alternative methods for evaluations of fracture toughness, were evaluated for each test. Responses are based either on a single value of load or energy absorbed in the test. The results indicate that (1) all seven computed responses are linearly related to crack length and the sensitivity to crack length is a function of both response parameter and material, and (2) precracking at either very high or very low levels of stress-intensity factor, Kf, are to be avoided. This work is the result of a study conducted by ASTM Task Group E-24.03.03 and members of eight participating laboratories.

    Keywords:

    aluminum, Charpy, crack size, fatigue precracking, fracture toughness, K, f, maximum, Kruskal-Wallis test, linear regression, notch preparation, precracking, statistical tests, steel, stress-intensity factor, titanium


    Author Information:

    Interrante, CG
    Senior MetallurgistStatistician in the Mathematical Analysis Division, U.S. Nuclear Regulatory CommissionNational Institute of Standards and Technology, WashingtonGaithersburg, DCMD

    Filliben, JJ
    Senior MetallurgistStatistician in the Mathematical Analysis Division, U.S. Nuclear Regulatory CommissionNational Institute of Standards and Technology, WashingtonGaithersburg, DCMD


    Paper ID: STP24144S

    Committee/Subcommittee: E28.94

    DOI: 10.1520/STP24144S


    CrossRef ASTM International is a member of CrossRef.