Hard and corrosion resistant multi principal element alloys based on Cr-Ti-V ternary system

• Fe and Si additions enhance hardness in Cr-Ti-V-based medium-entropy alloys. • Quaternary alloys achieve >450 HV without compromising corrosion resistance. • Microstructural evolution and phase stability studied via XRD and SEM/EDS. • Design approach balances mechanical strength and corrosion performance. This study investigated the microstructure, hardness and corrosion resistance of two novel quaternary Cr-Ti-V alloys containing Fe (Fe-CrTiV) and Si (Si-CrTiV), synthesized via arc melting. The Fe-CrTiV alloy contained a single-phase BCC solid solution, while Si-CrTiV consisted of Ti-Si Laves phase along with BCC solid solution phase. Both alloys revealed high hardness (466 HV for Fe-CrTiV and 677 HV for Si-CrTiV). Electrochemical testing in 0.6 mol/L NaCl solution revealed low corrosion current densities, a large passivation region, and excellent repassivation for both alloys. These findings suggest that quaternary alloying additions to Cr-Ti-V system can effectively tailor the alloy properties whilst maintaining corrosion resistance. The role of alloying additions on phase formation and resulting properties was discussed in comparison with already reported Al- and Ni-containing Cr-Ti-V alloys.