METHOD FOR DETERMINATION OF FATIGUE POINT OF MATERIAL Russian patent published in 2011 - IPC G01N3/32 

FIELD: machine building.

SUBSTANCE: method for determination of fatigue point of material for symmetrical cycle of loading consists in loading sample of analysed material by extension with continuous rate of straining upon preliminary single unloading from value of load equal to (σ_m+σ_B)/2 to zero value, in measuring time of repeated loading to stress (σ_m+σ_B)/2 and time until physical fracture of a sample. On base of ratio σ_-1=t_e/t_fσ_e there is evaluated the fatigue point. In ratio σ_-1 is fatigue point of material for symmetrical cycle of loading, t_e is time of development of elastic strain, t_f is time to physical fracture of the sample, σ_e is stress of elastic strain development equal to (σ_m+σ_B)/2.

EFFECT: upgraded accuracy of tests and increased efficiency at determination of fatigue point σ_-1 for symmetrical cycle of loading of elastic-ductile material.

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