Structure of single crystals of Ni-base superalloy after plastic deformation and heating

By means of electron microscopy, X-ray structure analysis, measurement of microhardness one investigated into the effect of the moderate (under creeping) and the intensive (shift under pressure) deformation on the structure and hardness of <001> monocrystals of nickel-base superalloy containing 0.16%C, 19% γ-alloying elements (Cr, Co, Mo, Re), 21% γ' - and carbidoforming elements (Ta, Nb, V, W, Al). One studied the peculiarities of recrystallization and phase transformations in the alloy upon various type deformation and heating. Deformation under creeping at 1000 deg C was determined to result information of lamellar γ/γ' - structure. At subsequent heating up to 700 deg C extra amount of γ'-phase was formed with no variation of dislocation structure. Under 1100-1200 deg C γ'-lamellas were dissolved and the dislocations were redistributed. Under 1220 deg C and higher in the volumes with complete dissolving of γ'-phase the alloy was crystallized. Shift under pressure at room temperature in monocrystals with lamellar and cubic γ'-phase resulted in variation of morphology of hardening particles. Recrystallization took place in gamma-phase at the absence of γ'-particles upon both the moderate and the intensive deformations