METHOD OF EVALUATING RESISTANCE OF WELDED LOW-CARBON STEEL ARTICLES TO STRESS-CORROSION CRACKING Russian patent published in 2014 - IPC G01N17/00 

FIELD: physics, testing.

SUBSTANCE: invention relates to investigation of resistance of metals and alloys to aggressive media and can be used particularly to evaluate reliability and longevity of welded pipes for building oil and gas pipelines. The disclosed method involves collecting a sample from the article from the region of the weld joint, making section from the sample, the surface of which is prepared by etching, and measuring microhardness on longitudinal lines situated on the outer seam, the centre and the inner seam. The average values of microhardness of the parent metal and the metal in the heat affected zone are then determined on each line. Further, the difference between said values and the average value of the difference in microhardness of the parent metal and the metal in the heat affected zone is determined, from which resistance of the weld joint to stress-corrosion cracking is determined.

EFFECT: faster and easier operations for obtaining reliable express evaluation of resistance of welded articles to stress-corrosion cracking.

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