METHOD FOR DETECTION OF MICROCRACKS IN METAL Russian patent published in 2013 - IPC G01N3/32 

FIELD: metallurgy.

SUBSTANCE: prepared surface of a metal specimen similar to metal of the investigated structure is influenced in three different zones with an indenter in the form of a pyramid, thus performing in each series of at least 50 indentions with the load value, at which the indent of the indenter does not exceed metal grain sizes, with indenter movement pitch providing the exclusion of action of deformation fields of the previous indention on the following one. Distribution of microhardness values is determined, out of which minimum microhardness values is determined, which is accepted as a basic minimum value for that metal. Similarly, microhardness measurements are made in the investigated section of the investigated structure from the same metal. As per measurement results, distribution of microhardness values is determined, which is compare to the obtained basic minimum microhardness value. Lower microhardness values in metal of the investigated structure in comparison to basic minimum microhardness value give evidence of available microcracks in the section of the investigated structure.

EFFECT: improving evaluation efficiency of technical state of metal of the structure and forecasting of its operating reliability.

2 dwg