STP1057

    Operator Errors in the Measurement of Microindentation Hardness

    Published: Jan 1989


      Format Pages Price  
    PDF (432K) 31 $25   ADD TO CART
    Complete Source PDF (2.4M) 31 $55   ADD TO CART


    Abstract

    An interlaboratory test program (“round-robin”) was conducted by ASTM Committee E-4 on Metallography to develop information for a Precision and Bias section for ASTM Test Method for Microhardness of Materials (E 384). Knoop and Vickers indents were made by one person using seven specimens of varying hardness and six test loads: 25, 50, 100, 200, 500, and 1000 gf (five indents of each type at each load on each specimen). These indents were measured by personnel at 24 laboratories. The results demonstrate substantial variability in hardness which increased with decreasing test load and increasing specimen hardness, that is, with decreasing diagonal length.

    Keywords:

    microhardness, microindentation hardness, Knoop hardness, Vickers hardness, load, precision, bias


    Author Information:

    Vander Voort, GF
    Supervisor, Metal Physics Research, Carpenter Technology Corp., Reading, PA


    Paper ID: STP25269S

    Committee/Subcommittee: E36.10

    DOI: 10.1520/STP25269S


    CrossRef ASTM International is a member of CrossRef.