METHOD OF PREDICTION OF PARAMETERS OF FATIGUE DESTRUCTION OF SHEET METAL MATERIALS Russian patent published in 2020 - IPC G01N3/32 G01N19/08 

FIELD: test.

SUBSTANCE: invention relates to fatigue testing of metal materials for determining cyclic durability, fatigue curve parameters and can be used to determine fatigue characteristics in wide durability areas. Cyclic loading to failure is carried out, number of loading cycles to failure at fixed voltage level is determined and correlations between level of cyclic stress and number of cycles before destruction are established. Tests are performed by soft net bending scheme in one plane at electromagnetic installation simultaneously with recording of information parameters of current deflection curves, along which duration of period before fatigue cracks formation is recorded, moment of crack occurrence and duration of material operation with crack. Tests are terminated after the sample leaves the resonance mode. Method comprises monotonously stretching a test specimen of sheet material to destruction, in order to open surface of formed crack in order to determine its length, and based on it fracture growth rate is determined, and fracture of sample is investigated under electron microscope and conclusion is made on character of destruction centre on material surface.

EFFECT: technical result is possibility of determining material which most meets operating requirements and provides reduced accident rate of metal structures of article.

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