METHOD FOR MEASURING THE DEPTH OF SURFACE CRACK BY ELECTRICAL POTENTIAL METHOD

FIELD: metallurgy.SUBSTANCE: invention relates to the field of non-destructive testing, it can be used to measure the depth of surface cracks in metals. The method of measuring the depth of a surface crack by the electrical potential method is as follows. Current electrodes 2 and 3 are installed at points T1and T2, located opposite each other on different sides relatively to crack 9. Contact points P1and P2of potential electrodes 4 and 5 are selected so that they are located one after the other on one of the sides of the crack and are displaced in one direction along the crack from line T1T2. Potential electrode 6 is installed at contact point P3, located on the other side of crack 9 relatively to points P1and P2. The first pair of potential electrodes connected to the first input of electronic unit 8 is formed between potential electrodes 4 and 5 installed at points P1and P2. The second pair of potential electrodes connected to the second input of electronic unit 8 is formed between potential electrodes 4 and 6 installed at points P1and P3. After installing the electrodes, the alternating sinusoidal electric current generated by source 1 is passed, introduced by current electrodes 2 and 3 at contact points T1, T2. VoltageUV1between electrodes 4 and 6 andUV2between electrodes 4 and 5 is measured using electronic unit 8. Ratio Re(UV1/UV2) is calculated from measured voltagesUV1andUV2and the depth of the crack is estimated by it. Ratio Re(UV1/UV2) is uniquely related to depth h of the crack and practically does not depend on the electromagnetic characteristics of the controlled object with the crack.EFFECT: increase in sensitivity to the depth of the crack and an increase in the range of its measurement.2 cl, 7 dwg Изобретение относится к области неразрушающего контроля и может быть использовано для измерения глубины поверхностных трещин в металлах. Способ измерения электропотенциальным методом глубины поверхностной трещины осуществляется следующим образом. Токовые электроды 2 и 3 устанавливают в точках T1и Т2, находящихся напротив друг друга по разные стороны относительно трещины 9. Выбирают точки контакта P1и P2потенциальных электродов 4 и 5 так, чтобы они находились друг за другом на одном из берегов трещины и были смещены в одном направлении вдоль трещины от линии Т1Т2. Устанавливают потенциальный электрод 6 в точке контакта Р3, расположенной на другом относительно точек P1и Р2берегу трещины 9. Первую пару потенциальных электродов, подключенную к первому