ИСТИНА

On the example of lamellar (~1 mm thick) samples of polycrystalline (grain size ~3 μm) commercially pure titanium (VT1-0 grade), it is shown that nanostructuring of thin (1–3 μm) near-surface layers by processing nanosecond laser pulses according to an optimized one, including Based on computer simulation data, the processing mode leads to a significant (up to two times) increase in the conditional endurance limit for high-cycle (up to 106 cycles) fatigue in the uniaxial loading mode (figure). Molecular dynamics modeling of the evolution of the structural phase state of hcp titanium under the action of laser-induced shock waves has been carried out. It has been established that the physical mechanism for the formation of a nanocrystalline structure in titanium under these conditions is the process of phase recrystallization, which is implemented as a chain of phase transformations from the initial hcp α-phase to the high-pressure ω-phase, and again to the initial α-phase. Limiting temperature (700K) is calculated; above which α --> ω the phase transition is not observed under the studied conditions.