In this study, GH4169 alloy(Corresponding to the US brand Inconel 718) was buried into NaCl-Na2SO4 mixed salts to carry out hot corrosion. The image processing technology were employed to analyze the morphology of the corrosion layer, in order to reveal the hot corrosion mechanism of the alloy in molten salt. The results indicate that the crucible type and corrosion temperature have a great influence on the hot corrosion rate, corrosion surface morphology and formation mechanism of corrosion layer. The hot corrosion rate is mainly controlled by temperature, Al cation concentration in molten salt, stress in corrosion layer and other factors. The characteristic information extracted from the surface morphology after hot corrosion is closely related to the hot corrosion temperature and time.
AkcaEGürselA. A Review on Superalloys and IN718 Nickel-Based INCONEL Superalloy. Periodicals Eng Nat Sci (PEN)2015; 3. doi:10.21533/pen.v3i1.43
2.
KanesundJBrodinHJohanssonS. High temperature corrosion influence on deformation and damage mechanisms in turbine blades made of IN-792 during service. Eng Fail Anal2020; 110: 104388.
3.
MeisnerKJOpilaEJ. Hot corrosion of shipboard gas turbine blades. Oxid Met2020; 94: 301–322.
4.
PradhanDShankar MahobiaGChattopadhyayK, et al.Salt induced corrosion behaviour of superalloy IN718. Mater Today Proc2018; 5: 7047–7054.
5.
SimonsELBrowningGVLiebhafskyHA. Sodium Sulfate in Gas Turbines. Corrosion -Houston Tx-1955; 11.
6.
BornsteinNSDeCrescenteMA. The role of sodium in the accelerated oxidation phenomenon termed sulfidation. Metall Mater Trans B1971; 2: 2875–2883.
7.
RizhangZYuZ, et al.Investigation of the mechanism of internal sulfide internal oxidation during hot corrosion of nickel based superalloys. Acta Metallica Sinica1985; 21: 39–116. (In Chinese).
8.
RappRA. Hot corrosion of materials: a fluxing mechanism?. Corros Sci2002; 44: 209–221.
9.
LuthraKL. Kinetics of the low temperature hot corrosion of Co-Cr-Al Alloys. J Electrochem Soc1985; 132: 1293–1298.
10.
SumnerJEncinas-OropesaASimmsNJ, et al.Type II hot corrosion: behavior of cmsx-4 and IN 738 LCas a function of corrosion environment. Mater Corros2014; 65: 188–196.
11.
SumnerJEncinas-OropesaASimmsNJ, et al.Type II hot corrosion: kinetics studies of CMSX-4. Oxid Met2013; 80: 553–563.
12.
MalacarneRMathieuSSiblaniM, et al.On the sulfation reaction of protective and transient oxides at 650 °C and its role in the low temperature hot corrosion mechanism. Corros Sci2023; 218: 111186.
13.
HenderyMLWhittakerMTCockingsBJ, et al.The Effect of Salt Composition on the Stress-Free and Corrosion-Fatigue Performance of a Fine-Grained Nickel-Based Superalloy. Corros Sci2022; 198. doi:10.1016/j.corsci.2022.110113
14.
GabbTPTelesmanJHazelB, et al.The effects of hot corrosion pits on the fatigue resistance of a disk superalloy. J Mater Eng Perform2010; 19: 77–89.
15.
FeiRWeiweiW, et al.Theoretical calculation of saturated vapor pressure of pure water and construction of controllable water vapor generator . Laborat Res Explor2016; 35: 56–59. (In Chinese).
16.
WangJZhangCLiZ, et al.Corrosion behavior of nickel-based superalloys in thermal storage medium of molten eutectic NaCl-MgCl2 in atmosphere. Sol Energy Mater Sol Cells2017; 164: 146–155.
17.
DongRLiuDZhangT, et al.Hot-corrosion behavior associated with the evolution of corrosion scales of a Ni-based superalloy in molten salts. Prog Nat Sci2021; 31: 486–492.
18.
JiangRZhangLCZhaoY, et al.Effects of hot corrosion on fatigue performance of GH4169 alloy. J Mater Eng Perform2021; 30: 2300–2308.
19.
MahobiaGSPauloseNSinghV. Hot corrosion behavior of superalloy IN718 at 550 and 650 °C. J Mater Eng Perform2013; 22: 2418–2435.
20.
PradhanDMahobiaGSChattopadhyayK, et al.Effect of surface roughness on corrosion behavior of the superalloy IN718 in simulated marine environment. J Alloys Compd2018; 740: 250–263.
21.
PradhanDMahobiaGSChattopadhyayK, et al.Severe hot corrosion of the superalloy IN718 in mixed salts of Na2SO4 and V2O5 at 700 degrees C. J Mater Eng Perform2018; 27: 4235–4243.
22.
GrégoireBMonteroXGaletzMC, et al.Correlations between the kinetics and the mechanisms of hot corrosion of pure nickel at 700 °C. Corros Sci2019; 155: 134–145.
23.
MrowecS. The problem of sulfur in high-temperature corrosion. Oxid Met1995; 44: 177–209.
24.
YaruSShuaiZDaileZ, et al.Effects of Cr, Al on hot corrosion behavior of low expansion Thermo Span superalloys. J Mater Res2014(8): 6. (In Chinese).
25.
PriymakEYGryzunovVI. Effect of temperature on the evolution of the process of oxidation of heating surfaces of tpp steam generators. Met Sci Heat Treat2011; 52: 617–619.
26.
HoangNDTranVD. Image processing-based detection of pipe corrosion using texture analysis and metaheuristic-optimized machine learning approach. Comput Intell Neurosci2019; 2019: 8097213.
27.
PatelNSPavlíkVBočaM. High-Temperature corrosion behavior of superalloys in molten salts – A review. Crit Rev Solid State Mater Sci2017; 42: 83–97.
28.
SatoYHaraMShinataY, et al.Effect of a small amount of hydrogen chloride on high temperature oxidation of nickel-chromium alloys. J Japan Inst Meta Mater1997; 61: 56–63.
29.
KumarSChattopadhyayKAlamZ, et al.Corrosion behavior of surface nanostructured IN718 superalloy at 650 degrees C. Mater Perform Characteriz2022; 11: 157–170.
30.
PrasharGVasudevH. Hot corrosion behavior of super alloys. Mater Today : Proce2020; 26: 1131–1135.
31.
SreedharGRajaVS. Hot corrosion of YSZ/Al2O3 dispersed NiCrAlY plasma-sprayed coatings in Na2SO4–10 wt.% NaCl melt. Corros Sci2010; 52: 2592–2602.
32.
SequeiraCACHockingMG. Hot corrosion of nimonic 105 in sodium sulfate-sodium chloride melts. Corrosion -Houston Tx-2012; 37: 392–407.
33.
LinsVFCCastroMMRDominguesRZ, et al.High temperature cyclic oxidation resistance of iron chromium base alloys. Chem Eng Technol2010; 33: 334–340.
34.
RiffardFBuscailHCaudronE, et al.Yttrium sol–gel coating effects on the cyclic oxidation behaviour of 304 stainless steel. Corros Sci2003; 45: 2867–2880.
35.
VialasNMonceauD. Substrate effect on the high-temperature oxidation behavior of a pt-modified aluminide coating. Part I: influence of the initial chemical composition of the coating surface. Oxid Met2006; 66: 155–189.
