METHOD FOR PREDICTING THE RESISTANCE TO CYCLIC LOADS OF PLATE AND BELLEVILLE SPRINGS FROM SPRING STEEL Russian patent published in 2021 - IPC G01N29/14 

FIELD: flaw detection.

SUBSTANCE: invention relates to the field of flaw detection and can be used as a method of non-destructive testing in assessing the technical condition of metal structures of objects. The test sample is loaded in two stages with a load until its maximum deformation with simultaneous recording of acoustic emission signals by the device on the first of which short-term compression is carried out three times to maximum deformation, on the second, the specimen is loaded with a constant load up to the maximum deformation and held for a certain time. At the first stage, when registering emission signals, at the same time, the rate of change in the signal energy is measured and the conditional efficiency factor К=lgV is calculated. At the second stage, loading and recording of emission signals of the test specimen is carried out with a constant load up to maximum deformation and holding the specimen at this load for up to 12 h with registration of the total acoustic emission to establish the dependence N_tot≤15 = N_thr where N_tot is the value of the total acoustic emission during exposure test specimen at maximum deformation, N_thr is the threshold value of the total acoustic emission. The insufficient relaxation resistance of the test specimen is judged by the excess of the threshold value N_thr = 15, and the tendency to brittle fracture at K_thr≥1 where K_thr is the threshold value of the conditional efficiency factor.

EFFECT: invention is aimed at improving accuracy and efficiency of the forecast with the determination of the specific time of operability of the springs in specific operating conditions, as well as the assessment of the probability of the type of destruction of the material under the action of cyclic loads: viscous, ductile-brittle or brittle.

1 cl, 2 dwg, 1 tbl