Abstract: An apparatus for measuring the degree of sensitization of metal articles comprises an electrochemical cell in which the potential of a test-piece of the article with respect to a reference electrode is made to vary linearly with time by feeding currents of suitable intensity from the passivation field to the activation field by means of the counter-electrode; a pair of electrodes moves along the test-piece surface with the respective electrode ends kept equidistant and disposed along an axis substantially perpendicular to the test-piece surface, one of them being in contact with said surface; by measuring the potential difference of this pair of electrodes as a function of their position, the local degree of sensitization of the test-piece is obtained.

Abstract: The invention relates to a probe for the continuous in-situ measurement of the rate of corrosion of pipes subjected to high temperatures or having highly resistive fluids flowing therethrough, by a measurement of the polarization resistance, characterized in that it comprises: electrodes of tubular form one of which is the working electrode, adapted to provide an extension of a pipeline, said electrodes being alternately spaced apart with dielectric spacers, means for connecting said electrodes to said pipeline between two sections of the pipeline, and resilient or nearly resilient gaskets to provide sealtightness between said electrodes, spacers, connectors and pipe sections.