METHOD FOR DETERMINING STRESSES IN THE MATERIAL DURING THERMAL FATIGUE TESTING Russian patent published in 2021 - IPC G01N3/60 

FIELD: testing.

SUBSTANCE: invention relates to methods for non-destructive control of stresses in the material of products subjected to temperature and force impact in tests simulating destruction thereof and can be used in the field of nuclear and thermal power engineering, heavy mechanical engineering. Substance: line marks are applied in the center and at the edges of the tested areas of the sample and the distances between the marks are measured. The sample is fixed in the loading mechanism ensuring constraint of free thermal expansion and compression thereof, and cyclic loading of the working part of the sample is executed by heating or cooling. The constrained sample is heated to a predetermined temperature in the selected test half-cycle, the sustaining mode is started and the distances between the marks are measured. The constraint is removed from the sample by releasing one of the heads thereof, the distances between the marks are re-measured and the stresses are calculated by the changes in the distances between the corresponding pairs of marks in the last two measurements using the elasticity moduli of the material considering the temperature dependence thereof in the areas of stress determination. The sample is re-constrained and the previously released head thereof is rigidly fixed, cyclic heating is activated and testing is continued until the next selected point of stress determination.

EFFECT: technical result of the invention is increased accuracy of stress determination.

1 cl, 3 dwg, 1 tbl