STUDY OF RESISTANCE TO CYCLIC DEFORMATION IN OLIGOAND SINGLE CRYSTALS OF FEMNNIALX (X = C, TI, CR, CRMO) ALLOYS WITH THE SUPERELASTICITY EFFECT

For the first time, the resistance to cyclic deformations under compression depending on the chemical composition, test temperature, and size d of β-phase particles was studied on oligo- and single crystals of FeMnNiAlX (X = C, Ti, Cr, CrMo) alloys with the superelasticity (SE) effect. It is shown that at a temperature of 298 K, oligo-crystals of the FeMnNiAlTi alloy are characterized by low resistance to cyclic loads, associated with the influence of grain boundaries on the martensite stabilization. Single crystals of the FeMnNiAlC alloy, oriented for compression along the [001] direction in the quenched state at test temperatures of 298 and 373 K, have high resistance to cyclic deformations when cycling up to 30 «load-unloading» cycles. Single crystals of the FeMnNiAlCr alloy with compression axis [001], aged at 473 K for 3 h, are characterized by low resistance to cyclic loads at 298 and 473 K. In [001]-oriented single crystals of the FeMnNiAlCr alloy, additionally alloyed with Mo and aged at 473 K for 3 h, the resistance to cyclic deformations depends on the test temperature and increases with increasing temperature from 297 to 573 K.