Effect of Si alloying on the structural, thermal expansion, and magnetic properties of FeCoNiAlSix high-entropy alloys

Influence of Si Addition on the Microstructures, Phase Assemblages and Properties in CoCrNi Medium-Entropy Alloy

“…Many researchers have studied and proved that the addition of Si element significantly alters the phase assemblages and enhances the alloy’s hardness, wear resistance, corrosion resistance, and oxidation resistance [ 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 ]. The FeCoNiCrSi x [ 11 ], Al 0.5 CoCrCuFeNiSi x [ 12 ], FeCoNiAlSi x [ 13 ], Al 0.3 CoCrFeNi [ 14 ], Fe 2.5 CoNiCu [ 15 ], and AlCoCuNi-based M/HEAs [ 16 ] undergo the transition from a closed-packed face-centered cubic (FCC) structure to a loose-packed body-centered cubic (BCC) structure with the increasing of Si content, thus leading to better hardness and wear resistance. As Si content increases, the, FeCoCrNiMoSi x [ 17 ], Co 0.2 CrAlNi [ 18 ], FeCrMnVSi x [ 19 ], and CoCrFeNiSi x [ 20 ] M/HEAs enhance the hardness and wear resistance through the introduction of Si-rich precipitation, such as Cr 3 Si, Si-Ni, and σ phase.…”

“…In previous work, we aimed to improve the combination of strength and ductility in the range of keeping the single FCC phase. Nevertheless, the increase in Si content usually influences the crystal structure to change the mechanical performance [ 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 ]. Therefore, now we focus on the transformation of the crystal structure and mechanical properties with increasing the Si content.…”

“…The systematic study of Si element on the microstructure and properties of CrCoNiSi x MEA is required in order to answer these questions. Furthermore, the Si element generally increases the wear properties of the alloy [ 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 ]; nevertheless, the wear properties and mechanisms of CrCoNiSi x MEA have not been studied.…”

“…Many researchers have studied and proved that the addition of Si element significantly alters the phase assemblages and enhances the alloy's hardness, wear resistance, corrosion resistance, and oxidation resistance [11][12][13][14][15][16][17][18][19][20][21][22]. The FeCoNiCrSi x [11], Al 0.5 CoCrCuFeNiSi x [12], FeCoNiAlSi x [13], Al 0.3 CoCrFeNi [14], Fe 2.5 CoNiCu [15], and AlCoCuNi-based M/HEAs [16] undergo the transition from a closed-packed face-centered cubic (FCC) structure to a loosepacked body-centered cubic (BCC) structure with the increasing of Si content, thus leading to better hardness and wear resistance. As Si content increases, the, FeCoCrNiMoSi x [17], Co 0.2 CrAlNi [18], FeCrMnVSi x [19], and CoCrFeNiSi x [20] M/HEAs enhance the hardness and wear resistance through the introduction of Si-rich precipitation, such as Cr 3 Si, Si-Ni, and σ phase.…”