Creep resistance and strain-rate sensitivity of a CoCrFeNiAl_0.3 high-entropy alloy by nanoindentation

Effect of synthesis temperature on the phase formation of NiTiAlFeCr compositionally complex alloy thin films

“…Regarding mechanical properties, FeNiCoCrMn [4][5][6][7] and FeNiCoCr [7,8] single phase HEAs display superior cryogenic [4,7] and room temperature performances [5,7] through solid solution strengthening [9], deformation twinning [4,7], strain hardening [4,7] and grain refinement strengthening [5,6]. On the other hand, CCAs exhibiting precipitation strengthening are of interest because the coherent L1 2 /B2 secondary phase formation in a FCC [10,11]/BCC [12,13] matrix contributes towards strength and creep resistance at elevated temperatures [12][13][14]. As examples, FeCoNiCrTi 0.2 [15] and AlCoCrFeNi 2.1 CCAs [16] have shown to exhibit promising room temperature 3 [15] and high temperature properties [16] in terms of high tensile [15] and compression strengths [16][17][18].…”

Understanding phase equilibria in high-entropy alloys: II. Atomic-scale study of incorporation of metallic elements in Cr carbides – Application to equilibrium with AlCrFeMnMo

“…The required ab initio calculations were performed with the VASP (Vienna Ab initio Simulation Package) software [13], using the Projector Augmented Wave mode [14] and the GGA approximation with the PBE functional [15,16]. The pseudopotentials used contained 6 and 4 valence electrons for Cr and C, and (3,8,7,6) valence electrons for (Al, Fe, Mn, Mo) respectively. The energy cutoff for the plane wave expansion was chosen equal to 560 eV throughout, and the k-point mesh was of Monkhorst-Pack [17] type with a 6×6x6 grid.…”

“…Trying to interpret these experimental facts, one is faced with a rather intricate situation: (i) Mo 23 C 6 is currently not referenced as a specific phase in crystallographic databases [8], which strikingly contrasts with the common crystal structure referenced for Cr 23 C 6 and Mn 23 C 6 , (ii) several attempts to evaluate and compare the relative ther New routes of explorations are currently being opened in metallurgy, due to the emergence of multi-principal-element metallic alloys, noticeably the so-called "high-entropy alloys" (HEAs). HEAs nowadays offer a wide, still largely unknown, class of materials with intriguingly outstanding thermochemical and mechanical properties, ranging from high strength [1] to corrosion or creep resistance [2,3]. Moreover, in connection with their reputedly high entropy, the stability of HEAs is strongly dependent on thermodynamic criteria [4].…”

Effect of Heat Treatment on the Corrosion Resistance of AlFeCoNiMo0.2 High-Entropy Alloy in NaCl and H2SO4 Solutions

“…All high-entropy alloys exist in solid solution form, usually in the form of single-phase FCC or single-phase BCC structures or mixed FCC and BCC phase compositions, and despite the inclusion of more significant elements, no complicated intermetallic compounds or brittle phases are formed between the elements [1][2][3][4]. High-entropy alloys have unique properties, such as high fracture toughness [5,6], high creep resistance [7,8], high oxidation and corrosion resistance [9,10], etc., due to the serious lattice distortion and slow diffusion effect that the solid-solution phase in HEAs possesses under this design concept. Corrosion resistance is a topic that is addressed in a variety of special service environment areas, including aerospace, nuclear engineering, marine engineering, and others.…”