NiCrxMoy(x=1,1.5;y=0,0.1,0.3)alloy coatings were prepared on the Q235 substrate by laser cladding under the protection of argon.The phase composition,microstructure,corrosion behavior,and mechanical properties of the ...NiCrxMoy(x=1,1.5;y=0,0.1,0.3)alloy coatings were prepared on the Q235 substrate by laser cladding under the protection of argon.The phase composition,microstructure,corrosion behavior,and mechanical properties of the NiCrxMoy alloy coatings were investigated using X-ray diffraction,scanning electron microscopy,transmission electron microscopy,electrochemical tests,X-ray photoelectron spectroscopy,microhardness,and nanoindentation tests.As the Cr content increased,the phase composition of the coatings changed from a single face-centered cubic(FCC)structure to a dual-phase structure coexisting with body-centered cubic(BCC)and FCC structures,while the addition of Mo promoted the precipitation ofσphase.The appearance of a homogeneous dual-phase structure and some amount ofσphase played a positive role in the corrosion resistance of NiCrxMoy coatings.Cr^3+ ions and Mo^6+ ions in the passive film enhanced the stability of the coatings.The nanoindentation tests showed that the nanohardness(6.71 GPa)and elastic modulus(184.40 GPa)of BCC phase were higher than those of the FCC phase(5.19 GPa and 155.26 GPa,respectively).Overall,the BCC phase andσphase improved the mechanical properties of the coatings.展开更多
基金financially supported by the Distinguished Taishan Scholars in Climbing Plan(No.tspd2O161OO6)the National Natural Science Foundation of China(Nos.51772176 and 51971121).
文摘NiCrxMoy(x=1,1.5;y=0,0.1,0.3)alloy coatings were prepared on the Q235 substrate by laser cladding under the protection of argon.The phase composition,microstructure,corrosion behavior,and mechanical properties of the NiCrxMoy alloy coatings were investigated using X-ray diffraction,scanning electron microscopy,transmission electron microscopy,electrochemical tests,X-ray photoelectron spectroscopy,microhardness,and nanoindentation tests.As the Cr content increased,the phase composition of the coatings changed from a single face-centered cubic(FCC)structure to a dual-phase structure coexisting with body-centered cubic(BCC)and FCC structures,while the addition of Mo promoted the precipitation ofσphase.The appearance of a homogeneous dual-phase structure and some amount ofσphase played a positive role in the corrosion resistance of NiCrxMoy coatings.Cr^3+ ions and Mo^6+ ions in the passive film enhanced the stability of the coatings.The nanoindentation tests showed that the nanohardness(6.71 GPa)and elastic modulus(184.40 GPa)of BCC phase were higher than those of the FCC phase(5.19 GPa and 155.26 GPa,respectively).Overall,the BCC phase andσphase improved the mechanical properties of the coatings.
