TESTING METHOD OF SAMPLES FROM MATERIAL UNDER STRESSING WITH HIGH TEMPERATURE Russian patent published in 2018 - IPC G01N3/18 

FIELD: test equipment.

SUBSTANCE: invention relates to methods for testing metals for stretching with a high heating temperature and can be used to determine the dependence of stress intensity on the degree and the rate of deformation, that must be taken into account in the technological calculations of the form-changing operations of isothermal punching of sheet metals. Essence: before the test, a measurement of the initial cross-sectional dimensions of the sample is made, fixing the sample in the grips of the testing machine and the heating device, installation of thermometer thermocouple of the sample, heating of the sample to the set temperature and holding time. Then the tensile test is carried out with the recording of the "load-transfer" diagram. In the process of stretching at the rate of movement of the gripping organ V₁ by an elongation value of 5÷10 % change the rate of movement of the gripping organ to the conveying speed V₂ without stopping the stretching process, the sample is stretched by the elongation value of 5÷10 % and again the rate of movement of the gripping device is changed to the speed V₃ etc. with the subsequent repetition of the cycle of switching of rates of moving of the gripping device in the process of stretching and obtaining a sawtoothlike "load-transfer" diagram on which at least three switching cycles of the rate movement of the gripping device are recorded.

EFFECT: accuracy increasing and reducing the labor intensity of the test by determining the dependence of the stress intensity from the degree and strain rate under tension with higher- temperature of the sample from metal.

1 cl, 5 dwg, 1 tbl