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The NiSiAlY material is a promising candidate to replace NiCrAlY,which can withstand the harsh salt-spray conditions in marine environment.To efficiently design novel NiSiAlY alloys,this work establishes a thermodynamic dataset of the Al-Ni-Si-Y quaternary system using the CALPHAD (CALculation of PHAse Diagrams) approach.We employ this database to calculate and predict the phase constitutions and solid-ification behaviors of different NiSiAlY alloys concerning the content variations of Al and Si.We have further proposed the selection of the NiSiAlY alloys for serving in marine salt-spray environment with three constraints:(i) outstanding mechanical property;(ii) good high-temperature anti-oxidation;(iii)excellent corrosion resistance.This results in a compositional range of the NiSiAlY alloys with 1 wt%< w(Si) < 5 wt%,11 wt% < w(Al) < 20 wt% and w(Y) =1 wt%,which corresponds the L12+bcc_B2+Ni5Y ternary phase region at temperatures ranging from ~500 to ~1000 ℃.Our predictions are validated by key experiments,suggesting that the model-based description of the Al-Ni-Si-Y system can serve as a guidance to design the novel NiSiAlY alloys in resisting harsh salt-spray environment.