STP1092: J-R Curve Testing Utilizing the Reversing Direct Current Electrical Potential Drop Method

    Bicego, V
    Chief of Fatigue and Creep Laboratory, researcher, Chief of Mechanics and Microstructural Section, and Chief of Fracture Mechanics Laboratory, CISE SpA, Segrate Milano,

    Liviero, D
    Chief of Fatigue and Creep Laboratory, researcher, Chief of Mechanics and Microstructural Section, and Chief of Fracture Mechanics Laboratory, CISE SpA, Segrate Milano,

    Fossati, C
    Chief of Fatigue and Creep Laboratory, researcher, Chief of Mechanics and Microstructural Section, and Chief of Fracture Mechanics Laboratory, CISE SpA, Segrate Milano,

    Lucon, E
    Chief of Fatigue and Creep Laboratory, researcher, Chief of Mechanics and Microstructural Section, and Chief of Fracture Mechanics Laboratory, CISE SpA, Segrate Milano,

    Pages: 24    Published: Jan 1990


    Abstract

    A Reversing Direct Current Electrical Potential Drop (RDCEPD) method has been implemented at CISE for crack monitoring in laboratory tests on specimens of metallic materials. Convenient features of the method are simple and cheap electronics, good insensitivity to noise from the environment, insensitivity to thermoelectrical potentials, and compensation for current and temperature fluctuations. The method is suitable for low-cycle fatigue crack initiation studies, fatigue, corrosion and creep crack growth tests, and J-integral tests. In the latter case, difficulties in obtaining reliable crack length values, due to resistivity changes in the plastically strained material of the specimen, are discussed on the basis of an experimental analysis on different types of steels.

    Keywords:

    electric potential drop, mechanical tests, cracks, elasto-plastic fracture mechanics, automation, fatigue testing, fracture testing


    Paper ID: STP25036S

    Committee/Subcommittee: E08.03

    DOI: 10.1520/STP25036S


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