A review on Corrosion of High Entropy Alloys: Exploring the Interplay Between Corrosion Properties, Alloy Composition, Passive Film Stability and Materials Selection

Nascimento, Camila Boldrini; Donatus, Uyime; Ríos, Carlos Triveño; Oliveira, Mara Cristina Lopes de; Antunes, Renato Altobelli

doi:10.1590/1980-5373-MR-2021-0442

Sumário Anterior Atual Seguinte

Sumário

Articles • Mat. Res. 25 • 2022 • https://doi.org/10.1590/1980-5373-MR-2021-0442 linkcopy

A review on Corrosion of High Entropy Alloys: Exploring the Interplay Between Corrosion Properties, Alloy Composition, Passive Film Stability and Materials Selection

Authorship SCIMAGO INSTITUTIONS RANKINGS

Abstract

The corrosion resistance of high entropy alloys was reviewed in the present work. The main focus was to explore the correlation between alloy composition, passive film stability and corrosion properties and use this information to develop a materials selection procedure based on the Ashby approach. Corrosion current densities and pitting potentials were the main design parameters used to rank different alloys, based on a careful examination of data published in the literature, considering uniform and localized corrosion, respectively. The outputs of the selection process clearly indicated a strong dependence of the corrosion resistance on passive film stability, although microstructural homogeneity and uniform distribution of alloying elements should not be disregarded. Proper combinations of elements such as Co, Al, Ti, Mo and Cr, especially, are effective at enhancing the corrosion resistance of high entropy alloys.

Keywords:
High entropy alloys; corrosion; passive film stability; materials selection

Alloy composition	Structure	E_corr (mV_SCE)	i_corr (µA.cm^-2)	i_pass (µA.cm^-2)	E_pit (mV_SCE)	Additional comments	Reference
CoCrFeNi	FCC	161	15.8	4.5	244	Electrolyte: 0.5 mol.L^-1 H₂SO₄ solution at RT	²⁶ ^-a
AlCoCrFeNi	FCC + BCC	148	13.1	13.9	252	Electrolyte: 0.5 mol.L^-1 H₂SO₄ solution at RT	²⁶ ^-b
Co_1.5CrFeNi_1.5Ti_0.5	FCC	150	30	9	1089	Interdendrites rich in Ti and Ni; dendrites rich in Fe and Cr; Electrolyte: 0.5 mol.L^-1 H₂SO₄ solution at RT	²⁸ ^-a
Co_1.5CrFeNi_1.5Ti_0.5Mo_0.8	FCC + Cr and Mo-rich sigma phase	172	69	22	1089	Interdendrites rich in Cr and Mo; dendrites rich in Co and Ni; Electrolyte: 0.5 mol.L^-1 H₂SO₄ solution at RT	²⁸ ^-b
CoCrFeNiMo_0.4	FCC + Cr and Mo-rich sigma phase	-289	0.712	6	88.5	Electrolyte: 0.5 mol.L^-1 H₂SO₄ solution at RT	³⁰
CoCr₂Ni₂AlTi	Two BCC phases + Al_xCo	-240	7.24	2.45	886	Electrolyte: 0.5 mol.L^-1 H₂SO₄ solution at RT	⁴² ^-a
Co₂Cr₂Ni₂AlTi	FCC + BCC + NiCoCr + Al_xCo	107	0.654	1.54	901		⁴² ^-b
CoCr₂Ni₃AlTi	Two BCC phases + FCC + Al_xCo	-102	4.3	2.23	936		⁴² ^-c
Fe₄₀Ni₂₀Co₂₀Cr₂₀	FCC	34	----	4.7	862	Electrolyte: 0.1 mol.L^-1 H₂SO₄ solution at RT	⁴⁵
Alloy composition	Structure	E_corr (mV_SCE)	i_corr (µA.cm^-2)	i_pass (µA.cm^-2)	E_pit (mV_SCE)	Additional comments	Reference
AlCuCoFeNi	FCC + BCC	-58	7.9	----	----	Cu-rich FCC phase; Al and Ni-rich BCC phase; Ti and Cr promoted grain refinement; Electrolyte: 0.5 mol.L^-1 H₂SO₄ solution at RT	⁵⁵-a
AlCoCuFeNiCr	BCC + FCC	-75	5.1	----	----		⁵⁵-b
AlCoCuFeNiTi	FCC+BCC+Laves	-253	44.8	----	----		⁵⁵-c
AlCoCuFeNiCrTi	FCC+BCC+Laves	-256	39.6	----	----		⁵⁵-d
AlCoCrFeNi	FCC + BCC + B2 (ordered BCC)	-188	30.4	2.12	1008	Annealed at 1100°C for 48 h and quenched in water; Cr enriched in the BCC phase; Electrolyte: 0.5 mol.L^-1 H₂SO₄ solution at RT	⁵⁶
FeCoCrNiAl_0.3	FCC	-294	17.93	2.58	901	Electrolyte: 0.5 mol.L^-1 H₂SO₄ solution at RT	⁵⁷
AlCoCrFeNiTi_0.5	----	-100	0.57	26	950	Electrolyte: 0.5 mol.L^-1 H₂SO₄ solution at RT	⁵⁸
CoFeCrNi	FCC	-250	----	4.63	----	Mn degraded passive film stability; Electrolyte: 0.1 mol.L^-1 H₂SO₄ solution at RT	⁵⁹-a
CoFeCrNiMn	FCC	-320	----	4.37	----		⁵⁹-b
(CoFeNiMn)₇₅Cr₂₅	FCC	-310	----	4.33	----		⁵⁹-c
(CoFeNi)₈₀Cr₂₀	FCC	-240	----	3.59	----		⁵⁹-d
CrMnFeNi	FCC	26	191	----	1568	Homogeneous element distribution in dendrites and interdendrites; Electrolyte: 0.5 mol.L^-1 H₂SO₄ solution at RT	⁶⁰-a
CrMnFeNiLa_0.1	FCC	73	338	----	1346		⁶⁰-b

Alloy composition	Structure		E_corr (mV_SCE)		i_corr (µA.cm^-2)		i_pass (µA.cm^-2)		E_pit (mV_SCE)		Additional comments		Reference
CoCrFeNi	FCC		-234		----		4.0		----		Electrolyte: 3.5 wt.% NaCl solution at RT		¹⁷ ^-a
CoCrFeNiAl	BCC + B2 (ordered BCC)		-300		----		6.3		667		Electrolyte: 3.5 wt.% NaCl solution at RT		¹⁷ ^-b
Al_0.3CoCrFeNi	FCC		-195		0.0835		1.24		460		Increasing Al content reduces the corrosion resistance (thicker, less stable passive film); Electrolyte: 3.5 wt.% NaCl solution at RT		²⁷
CoCrFeNiMo_0.4	FCC + Cr and Mo-rich sigma phase		-261		0.082		16		948		Electrolyte: 3.5 wt.% NaCl solution at RT		³⁰
FeCoNiCr_0.5	FCC		-319		2.36		----		453		Electrolyte: 3.5 wt.% NaCl solution at RT		³¹
AlCr_2.5FeNi₂Cu_1.6	FCC + BCC		-516		1.25		----		-21		Electrolyte: 3.5 wt.% NaCl solution at RT		³⁴
CoCrFeMnNi	FCC		-230		0.14		----		----		Electrolyte: 3.5 wt.% NaCl solution at RT		³⁷
Al₂CrFeCoCuTiNi	FCC + BCC		-220		13		----		----		Increasing Ni contents reduced the corrosion resistance; Electrolyte: 3.5 wt.% NaCl solution at RT		⁴⁰ ^-a
Al₂CrFeCoCuTiNi₂	FCC + BCC		-500		67		----		----				⁴⁰ ^-b
Al₂CrFeCo_1.0CuNiTi	----		-220		0.013		----		No passivity breakdown up to 1.2 V_SCE		Laser-cladded coatings on Q235 steel substrate; Electrolyte: 3.5 wt.% NaCl solution at RT		⁴³ ^-a
Al₂CrFeCo_1.5CuNiTi	----		-510		0.074		----		No passivity breakdown up to 1.2 V_SCE				⁴³ ^-b
Alloy composition	Structure		E_corr (mV_SCE)		i_corr (µA.cm^-2)		i_pass (µA.cm^-2)		E_pit (mV_SCE)		Additional comments		Reference
Co₂CrCuFeMnNi	Two FCC phases		-787		6.95		----		19		Sintered alloy; the FCC phase with higher Co content is more resistant to corrosion; Electrolyte: 3.5 wt.% NaCl solution at RT		⁴⁴
CrMnFeCoNi	FCC		142.5		0.105		----		460		Cr-depleted interdendrites are the starting point for corrosion; Electrolyte: 3.5 wt.% NaCl solution at RT		⁶¹
(CoCrFeNi)₉₅Nb₅	FCC		-128		7.23		41.3		502		Plasma sprayed coating on Q235 steel substrate; Electrolyte: 3.5 wt.% NaCl solution at RT		⁶²
Al_0.9CoCrFeNi	FCC + BCC + B2 (ordered BCC)		-216		0.093		----		164		Electrolyte: 3.5wt.% NaCl solution at RT		⁶³ ^-a
Al_0.9CoCrFeNiTi_0.5	BCC + B2 (ordered BCC) + Fe-Cr sigma phase		-347		0.310		----		184		Electrolyte: 3.5wt.% NaCl solution at RT		⁶³ ^-b
CoCrFeNi₂	FCC		-290		0.129		----		320		Mo enrichment in the passive film reduces pitting corrosion susceptibility; Electrolyte: 3.5 wt.% NaCl solution at RT		⁶⁴ ^-a
CoCrFeNi₂Mo_0.25	FCC + HCP		-260		0.125		----		910				⁶⁴ ^-b
(Fe-Co-Ni)₁₅(Al-Ti-Zr)₈₅	FCC + amorphous phase		-460		2.046		----		----		Multi-component films obtained by sputtering on Si substrate; Electrolyte: 3.5 wt.% NaCl solution at RT		⁶⁵ ^-a
(Fe-Co-Ni)₂₀(Al-Ti-Zr)₈₀	FCC + amorphous phase		-281		0.586		----		----				⁶⁵ ^-b
(Fe-Co-Ni)₂₅(Al-Ti-Zr)₇₅	FCC + amorphous phase		-260		0.062		----		----				⁶⁵ ^-c
Alloy composition	Structure		E_corr (mV_SCE)		i_corr (µA.cm^-2)		i_pass (µA.cm^-2)		E_pit (mV_SCE)		Additional comments		^Reference
Al_0.3Cr_0.5FeCoNi	FCC		-185		0.1		----		350		Increasing the Cr content in the alloy, the FCC and BCC phases became enriched with Cr; Electrolyte: 3.5 wt.% NaCl solution at RT		⁶⁶ ^-a
Al_0.3Cr₂FeCoNi	FCC + BCC + B2 (ordered BCC)		-99		0.01		----		No breakdown up to 2 V_SCE				⁶⁶ ^-b
TiCrVNb_0.5Al_0.5	BCC		-450		0.089		----		1950		Uniform distribution of elements without segregation; Electrolyte: 3.5 wt.% NaCl solution at RT		⁶⁷
Al_0.5CoCrFeNi	FCC		-570		0.17		----		130		As-cast condition; Electrolyte: 3.5 wt.% NaCl solution at RT		⁶⁸
CoCrFeNiMo_0.2	FCC		-192		0.00184		----		827		Mo enhances passivity (passive film composition not shown); Electrolyte: 3.5 wt.% NaCl solution at RT		⁶⁹
(CoCrFeNi)₉₈Mo₂	FCC		-191		0.07		----		----		Aging at 900 °C for 16 h, followed by water quenching; Co and Fe-rich dendrites; Cr and Mo-rich interdendrites; Electrolyte: 3.5 wt.% NaCl solution at RT		⁷⁰ ^-a
(CoCrFeNi)₉₈Mo₃	FCC + Mo-rich precipitates		-194		0.22		----		----				⁷⁰ ^-b
AlCoCrFeNiCu_0.5	FCC + BCC		-282		1.77		----		----		Equiaxed grains (grain size smaller than 30 µm); no Cu segregation in grain boundaries; Electrolyte: artificial seawater		⁷¹
Alloy composition		Structure		E_corr (mV_SCE)		i_corr (µA.cm^-2)		i_pass (µA.cm^-2)		E_pit (mV_SCE)		Additional comments		Reference
CoCrFeNi		FCC		-238		----		----		575		Sn increases the corrosion resistance of CoCrFeNi, whereas Al and Cu decrease; Electrolyte: 3.5 wt.% NaCl solution at RT		⁷² ^-a
CoCrFeNiAl		BCC + B2 (ordered BCC)		-303		----		----		316				⁷² ^-b
CoCrFeNiCu		FCC (matrix) + Cu-rich FCC (Cu segregation)		-161		----		----		-50				⁷² ^-c
CoCrFeNiSn		FCC + HCP		-233		----		----		1118				⁷² ^-d
CoFeMn_1.2NiGa_0.8		FCC + BCC		-416		1.11		----		790		Electrolyte: 3.5 wt.% NaCl solution at RT		⁷³
Al₁₀Co₂₄Cr₁₀Fe₁₅Ni₃₄Ti₆Cu₁		FCC		-63		0.022		----		----		Fe, Co and Cr enriched in the dendrite region; Al and Ti enriched in the interdendrite region; Electrolyte: 3.5 wt.% NaCl solution at RT		⁷⁴
CoCrFeNiGe_0.3		FCC		-34		0.56		2.51		1410		GeO₂ oxide present in the passive film increases the corrosion resistance with respect to CoCrFeNi HEA; Electrolyte: 3.5 wt.% NaCl solution at RT		⁷⁵
Co₃₀Cr₂₀Fe₃₀Ni₂₀		----		12		2.32		2.01		970		Electrolyte: 3.5 wt.% NaCl solution at RT		⁷⁶
Ni₂CrFeMo_0.2		----		-179		0.896		5.404		920				⁷⁷

Design requirements
Function	Structural component
Constraints	Acidic or sodium chloride electrolytes
Objectives	To maximize the corrosion resistance
Free variables	Component size and section area; choice of material

location_on

ABM, ABC, ABPol UFSCar - Dep. de Engenharia de Materiais, Rod. Washington Luiz, km 235, 13565-905 - São Carlos - SP- Brasil. Tel (55 16) 3351-9487 - São Carlos - SP - Brazil
E-mail: pessan@ufscar.br

rss_feed Acompanhe os números deste periódico no seu leitor de RSS