Precipitation-driven metastability engineering of carbon-doped CoCrFeNiMo medium-entropy alloys at cryogenic temperature

Novel Co-Cu-Based Immiscible Medium-Entropy Alloys with Promising Mechanical Properties

“…Meanwhile, the B2 and Cu-rich FCC phases in the 15Al alloy are revealed as dendritic and interdendritic microstructures. If we assume the dendritic B2 precipitates as an equiaxed precipitate, the contribution of precipitation strengthening in the 15Al alloy is quantified, as follows [10]:…”

“…The initial concept of HEAs is defined as a single phase with equiatomic or near-equiatomic compositions [1]. However, the range of alloy design in HEA/MEAs has been expanded to non-equiatomic and/or multiphase alloys [8][9][10][11][12][13][14][15][16][17][18][19][20][21]. Recently developed ferrous MEAs are representative types of non-equiatomic MEAs [8], which utilize phase metastability, resulting in transformationinduced plasticity.…”

“…Recently developed ferrous MEAs are representative types of non-equiatomic MEAs [8], which utilize phase metastability, resulting in transformationinduced plasticity. Meanwhile, the design of multiphase HEAs/MEAs to enhance yield Metals 2021, 11, 238 2 of 13 strength (YS) is widely adopted through precipitation [9][10][11][12][13][14], martensitic transformation [10,15,16], and eutectic reaction [17][18][19][20][21]. In particular, many research groups focus on heterogeneous HEAs developed by the formation of multiple domains using heterogeneities in composition [22,23], grain size [24,25], and crystal structure [17][18][19]26].…”

Isotropic and Kinematic Hardening of a High Entropy Alloy

“…A surge in research activity in this area can be traced back to the publication of two seminal papers [2,3] in 2004. To date, it has been reported that single-and multi-phase HEAs with a face-centered cubic (FCC) and/or body-centered cubic (BCC) crystal structure exhibit outstanding mechanical properties with their distinct deformation behavior [4] in the temperature range from cryogenic [5][6][7][8] to ambient [9][10][11] and elevated temperatures [12,13]. Furthermore, excellent surface properties such as corrosion resistance [14][15][16], wear resistance [17,18], and oxidation resistance [19] have boosted research in the field of HEAs.…”

“…This communication aims at elucidating the evolution of both principal 4 elements of strain hardening: isotropic hardening (associated with the evolution of the dislocation density) and the kinematic hardening (related to back stress) as exemplified by the Bauschinger effect studied for an equiatomic CoCrFeMnNi alloy. 5 An ingot of HEA Co20Cr20Fe20Mn20Ni20 (at%) was prepared using vacuum induction melting in argon atmosphere. The purity of the alloying elements for casting was above 99.9%.…”