A multi-component nanocrystalline FeCrV alloy with improved mechanical properties and excellent irradiation resistance

An equiatomic low-activated FeCrV ternary alloy was prepared by mechanical alloying and spark plasma sintering. The BCC solid solution alloy exhibited an excellent strength-ductility synergy properties, which was 1.85 ​GPa compressive yield strength, 3.04 ​GPa fracture strength and more than 28% plasticity at room temperature. Even at an elevated temperature of 600 ​°C, its yield strength was still more than 1 ​GPa, revealing a pronounced high temperature resistance. The FeCrV alloy had a homogeneous microstructure with high-density dislocations. A nanocrystalline characteristic was demonstrated and the average grain size was about 322 ​nm, leading to the improved mechanical properties. The strengthening mechanism was discussed in detail and the contributions of strengthening factors were calculated. The FeCrV alloy was irradiated up to 160 dpa with 2 ​MeV Au2+ ions at 573 ​K. The nanoindentation test was carried out to simply evaluate the hardening degree under such a high dose irradiation with heavy ions. The semi-quantitative analysis results show that FeCrV alloy has an excellent irradiation tolerance compared with pure Fe.