Stainless steel (SS) 410 is widely used in many components of nuclear reactors due to its good corrosion resistance and high strength. However, wear is a major issue of these components due to its continuous sliding. ...Stainless steel (SS) 410 is widely used in many components of nuclear reactors due to its good corrosion resistance and high strength. However, wear is a major issue of these components due to its continuous sliding. SS 420 and Colmonoy 5 particles were deposited over SS 410 substrate by laser cladding process. Then, X-ray diffraction was used to find the phases present after cladding process. Further, coating morphologies were analysed by scanning electron microscopy (SEM) twinned with energy-dispersive spectroscopy. The obtained morphology indicates the hard laves phase present in the Colmonoy 5 cladding surface and needle-like structure in SS 420 cladding surface. Then, Vickers microhardness test was carried out in order to study the hardness and load-carrying capacity of the cladding specimen. Among those, Colmonoy 5 cladding specimen provide higher hardness due to the presence of laves phase formation. Then, the dry sliding wear study was conducted to calculate the mass loss after 2500 m of sliding. The combined effect of hardness and laves phase formation were reflected in dry sliding wear study analysis of the specimens. Then, to study the wear mechanism and roughness, worn surface morphologies were captured using SEM and white light interferometer, respectively.展开更多
To clarify the corrosion behavior of Ni-based hard facing alloy Colmonoy 56 and the preferential dissolution detail at the micrometer scale,the microstructure and the elemental distribution of a rod were analyzed,foll...To clarify the corrosion behavior of Ni-based hard facing alloy Colmonoy 56 and the preferential dissolution detail at the micrometer scale,the microstructure and the elemental distribution of a rod were analyzed,followed with the polarization measurement in aqueous solution with different p H and Na Cl concentrations.This rod has Fe-,Si-,and Cr-solutioned[Ni]matrix with heterogeneously dispersed secondary phases of Cr_(23)C_(6),CrB,Cr_(2)B,and Cr_(5)B_(3).The polarization curve largely changed with different p H:active in acid solution and passive in neutral and alkaline solution.The strongest passivation appeared at p H=11.Cl^(-)promoted the corrosion attack to the[Ni]matrix.In the case of pH=11,Cl^(-)caused the fast climb of anodic current from passivation at a less noble potential.Preferential dissolution of the[Ni]matrix occurred in most solutions,except in the case of pH=14 without Na Cl,in which the secondary phases preferably dissolved.展开更多
基金Ministry of Science and Technology(MOST),Taiwan,China,for providing financial support to carry out this research work.
文摘Stainless steel (SS) 410 is widely used in many components of nuclear reactors due to its good corrosion resistance and high strength. However, wear is a major issue of these components due to its continuous sliding. SS 420 and Colmonoy 5 particles were deposited over SS 410 substrate by laser cladding process. Then, X-ray diffraction was used to find the phases present after cladding process. Further, coating morphologies were analysed by scanning electron microscopy (SEM) twinned with energy-dispersive spectroscopy. The obtained morphology indicates the hard laves phase present in the Colmonoy 5 cladding surface and needle-like structure in SS 420 cladding surface. Then, Vickers microhardness test was carried out in order to study the hardness and load-carrying capacity of the cladding specimen. Among those, Colmonoy 5 cladding specimen provide higher hardness due to the presence of laves phase formation. Then, the dry sliding wear study was conducted to calculate the mass loss after 2500 m of sliding. The combined effect of hardness and laves phase formation were reflected in dry sliding wear study analysis of the specimens. Then, to study the wear mechanism and roughness, worn surface morphologies were captured using SEM and white light interferometer, respectively.
文摘To clarify the corrosion behavior of Ni-based hard facing alloy Colmonoy 56 and the preferential dissolution detail at the micrometer scale,the microstructure and the elemental distribution of a rod were analyzed,followed with the polarization measurement in aqueous solution with different p H and Na Cl concentrations.This rod has Fe-,Si-,and Cr-solutioned[Ni]matrix with heterogeneously dispersed secondary phases of Cr_(23)C_(6),CrB,Cr_(2)B,and Cr_(5)B_(3).The polarization curve largely changed with different p H:active in acid solution and passive in neutral and alkaline solution.The strongest passivation appeared at p H=11.Cl^(-)promoted the corrosion attack to the[Ni]matrix.In the case of pH=11,Cl^(-)caused the fast climb of anodic current from passivation at a less noble potential.Preferential dissolution of the[Ni]matrix occurred in most solutions,except in the case of pH=14 without Na Cl,in which the secondary phases preferably dissolved.
