THERMOELECTRIC METHOD OF NON-DESTRUCTIVE TESTING OF QUALITY OF SURFACE METAL LAYER Russian patent published in 2013 - IPC G01N25/72 

FIELD: metallurgy.

SUBSTANCE: two groups of similarly heated electrodes from one material are used; one group of heated electrodes is installed on the tested product, and the other one is installed on a reference specimen; difference thermo-emf is measured, which occurs at contact of the first group of heated electrodes with the tested product and the second group of heated electrodes with the reference; the quality of surface layer is judged by its value; with that, first, temperature of the tested product is measured, by means of which the temperature of groups of heated electrodes is changed so that the difference thermo-emf used during measurement between the first group of heated electrodes and the tested product, as well as between the second group of heated electrodes and the reference can remain the same at any temperature oscillations of the tested product and the reference; after that, difference thermo-emf is measured.

EFFECT: elimination of influence of the tested product temperature on the value of difference thermo-emf.

1 dwg, 1 tbl