Analysis of the temperature-dependent plastic deformation of single crystals of quinary, quaternary and ternary equiatomic high- and medium-entropy alloys of the Cr-mn-fe-co-ni system

Figures & data

Table 1. Single crystal growth methods, homogenization temperatures and chemical compositions (in atomic percentage) after homogenization of the equiatomic alloys investigated in this study.

Equiatomic alloys	Single crystal growth method	Homogenization temperature (K)	Cr	Mn	Fe	Co	Ni
CrMnFeCoNi^[Citation18]	Bridgman	1473	20.39	19.81	19.79	19.95	20.06
MnFeCoNi	Bridgman	1273	-	26.61	24.51	24.34	24.54
CrMnCoNi	Bridgman	1273	26.91	24.74	-	24.90	23.45
MnFeNi	Bridgman	1273	-	32.09	35.61	-	32.30
MnCoNi	Bridgman	1273	-	32.09	-	34.44	33.47
CrFeCoNi^[Citation19]	Floating zone	1473	25.11	-	24.83	25.32	24.74
CrCoNi^[Citation20]	Floating zone	1473	33.65	-	-	33.22	33.13
CrFeNi	Floating zone	1473	33.82	-	34.03	-	32.15
FeCoNi	Floating zone	1473	-	-	33.44	33.49	33.07

Table 2. CRSSs at 77 K (liquid nitrogen temperature) (τ_LN) and room temperature (τ_RT) of single crystals of the quinary, equiatomic HEA Cr-Mn-Fe-Co-Ni and its equiatomic quaternary and ternary MEAs. Data for single crystals of the equiatomic Cr-Mn-Fe-Co-Ni, Cr-Fe-Co-Ni and Cr-Co-Ni are from the indicated references. CRSS of polycrystals are all deduced from the yield strengths in Ref. [15] and other indicated references by dividing them by the Taylor factor of 3.06.

	Single crystals			Polycrystals^[Citation15]
Equiatomic alloys	τLN (MPa)	τRT (MPa)	τLN/τRT	τLN (MPa)	τRT (MPa)	τLN/τRT
CrMnFeCoNi	109^[18]	43^[18]	2.53	126^[26]	62^[26]	2.03
	153^[26]	56^[26]	2.73
MnFeCoNi	84	44	1.91	98	58	1.69
CrMnCoNi	142	71	2.00	164	92	1.77
CrFeCoNi	102^[20]	44^[20]	2.32	156	91	1.72
	96^[25]	41^[25]	2.34
CrCoNi	133^[19]	60^[19]	2.22	168	99	1.69
	157^[27]	78^[27]	2.01
CrFeNi	111	50	2.22	126^[23]	57^[23]	2.21
MnFeNi	104	52	2.00	120	75	1.61
MnCoNi	98	53	1.85	121	75	1.61
FeCoNi	95	49	1.94	112	70	1.60

Table 3. The experimental 0 K CRSS values for single crystals of the quinary HEA and its derivative quaternary and ternary equiatomic alloys determined by fitting the CRSS-temperature curves to Eq. (1) from which the optimal parameters (1/p and 1/q) were obtained. Results for equiatomic Cr-Mn-Fe-Co-Ni, Cr-Fe-Co-Ni and Cr-Co-Ni are from previous studies [18-20].

	Single crystals								Polycrystals^[Citation15,Citation16,Citation23,Citation26]
Equiatomic alloys	τ0 (MPa)	Δτ0 (MPa)	Tc (K)	Ta (K)	τath (MPa)	τth (MPa)	1/q	1/p	σ0 (MPa)	1/q	1/p
CrMnFeCoNi	197	41	77	873	18.7	154.8	0.58	2.70	525	0.87	2.44
MnFeCoNi	124	7	50	773	27.1	96.5	0.67	2.19	375	0.86	2.17
CrMnCoNi	253	48	77	773	31.5	221.4	0.50	1.86	650	0.89	2.44
CrFeCoNi	200	48	77	873	18.1	181.8	0.50	2.20	641	0.85	2.70
CrCoNi	225	56	62	873	27.8	197.2	0.66	2.67	661	0.90	2.70
CrFeNi	199	47	77	873	16.6	182.6	0.51	1.99	626	0.73	2.62
MnFeNi	150	25	60	773	36.3	114.2	0.73	2.32	448	0.94	2.63
MnCoNi	138	21	77	873	35.8	102.0	0.67	2.27	466	0.91	2.70
FeCoNi	132	15	77	873	15.9	116.5	0.77	2.23	418	0.94	2.33

Table 4. The increase in CRSS, starting temperature and peak temperature related to PL effect for equiatomic quinary Cr-Mn-Fe-Co-Ni HEA and its derivative quaternary and ternary alloys. The melting temperatures for these alloys are also listed.

	Δτ (MPa)	τd (MPa)	cMn	cFe	Starting temperature (Ts)(K)	Peak temperature (K)	Melting temperature^[Citation15,Citation23] (Tm)(K)	Ts/Tm
CrMnFeCoNi	4.2	3.23	0.20	0.20	873	1273	1553	0.56
MnFeCoNi	5.5	6.78	0.25	0.25	673	1073	1533	0.44
CrMnCoNi	1.5	4.33	0.25	0.00	773	1173	1489	0.52
CrFeCoNi	2.0	0.26	0.00	0.25	873	1273	1695	0.52
CrCoNi	1.8	0.00	0.00	0.00	873	1173	1690	0.52
CrFeNi	3.0	0.10	0.00	0.33	873	1173	1666	0.52
MnFeNi	11.4	3.94	0.33	0.33	673	1073	1473	0.46
MnCoNi	3.9	7.28	0.33	0.00	773	1073	1462	0.53
FeCoNi	1.9	0.50	0.00	0.33	973	1173	1724	0.56

Table 5. The apparent activation volumes at 0 K, 77 K (liquid nitrogen temperature, V_LN) and room temperature for single crystals of the quinary HEA and its derivative quaternary and ternary equiatomic alloys.

	cCr	cMn	V0 (b^3)	VLN (b^3)	VRT (b^3)
CrMnFeCoNi^[Citation18]	0.20	0.20	23	40	234
MnFeCoNi	0.00	0.25	47	62	268
CrMnCoNi	0.25	0.25	21	37	190
CrFeCoNi^[Citation20]	0.25	0.00	22	40	249
CrCoNi^[Citation19]	0.33	0.00	20	36	131
CrFeNi	0.33	0.00	19	34	251
MnFeNi	0.00	0.33	45	71	277
MnCoNi	0.00	0.33	38	51	259
FeCoNi	0.00	0.00	34	55	257

Kawamura M, Asakura M, Okamoto NL, et al. Plastic deformation of single crystals of the equiatomic Cr−Mn−Fe−Co−Ni high-entropy alloy in tension and compression from 10 K to 1273 K. Acta Mater. 2021;203:116454. DOI: 10.1016/j.actamat.2020.10.073.

 Web of Science ®Google Scholar

Li L, Chen Z, Kuroiwa S, et al. Tensile and compressive plastic deformation behavior of medium-entropy Cr-Co-Ni single crystals from cryogenic to elevated temperatures. Int J Plast. 2022;148:103144. DOI: 10.1016/j.ijplas.2021.103144.

 Web of Science ®Google Scholar

Li L, Chen Z, Yuge K, et al. Plastic deformation of single crystals of the equiatomic Cr-Fe-Co-Ni medium entropy alloy – A comparison with Cr-Mn-Fe-Co-Ni and Cr-Co-Ni alloys. Int J Plast. 2023;169:103732. DOI: 10.1016/j.ijplas.2023.103732.

 Web of Science ®Google Scholar

Wu Z, Bei H, Pharr GM, et al. Temperature dependence of the mechanical properties of equiatomic solid solution alloys with face-centered cubic crystal structures. Acta Mater. 2014;81:428–441. DOI: 10.1016/j.actamat.2014.08.026.

 Web of Science ®Google Scholar

Inui H, Kishida K, Li L, et al. Uniaxial mechanical properties of face-centered cubic single- and multiphase high-entropy alloys. MRS Bull. 2022;47;168–174. DOI: 10.1557/s43577-022-00280-y.

 Web of Science ®Google Scholar

Schneider M, Laplanche G. Effects of temperature on mechanical properties and deformation mechanisms of the equiatomic CrFeNi medium-entropy alloy. Acta Mater. 2021;204:116470. DOI: 10.1016/j.actamat.2020.11.012.

 Web of Science ®Google Scholar

Abuzaid W, Sehitoglu H. Critical resolved shear stress for slip and twin nucleation in single crystalline FeNiCoCrMn high entropy alloy. Mater Charact. 2017;129:288–299. DOI: 10.1016/j.matchar.2017.05.014.

 Web of Science ®Google Scholar