Extra Strengthening and Work Hardening in Novel Precipitation‐Hardened FeCrNiSi_x Medium‐Entropy Alloys

Abstract

Precipitation strengthening is believed as an important strengthening method that optimizes the strength of alloys. Herein, the possibility of precipitation strengthening is demonstrated by introducing the intermetallic (Cr, Si)‐rich σ phase in the novel FeCrNiSix MEAs system. It is found that simultaneous enhancement in strength and work hardening can be attained by adding Si element in the FeCrNi MEA. Specifically, the FeCrNiSi0.2 alloy realizes a good balance of strength and ductility due to the precipitation of ultrafine‐ or even nanoscale‐sized σ phase. Moreover, quantitative analyses are conducted to assess the underlying strengthening mechanisms.

Designing Eutectic High‐Entropy Alloys Containing Nonmetallic Elements

“…However, for VBSi–EHEA, V and B elements were enriched and the Si element was depleted in M 3 B 2 ‐type boride, which was slightly different from our initial design idea. A previous study by Chang [ 43 ] and Bai [ 51 ] also indicated that Si had a large solid solubility in FCC‐disordered solid solution. By adding 0.3Si, CoCrNi and CoFeNi HEAs still maintained a single‐phase FCC‐disordered solid‐solution structure in the as cast.…”