The Al-based amorphous and nanocrystalline composite coatings with the composition of Al-Ni-Y-Co and Al-Ni-Mm-Fe were prepared on AZ91 Mg-based alloys by high velocity arc spraying technique(HVAS).The structure charac...The Al-based amorphous and nanocrystalline composite coatings with the composition of Al-Ni-Y-Co and Al-Ni-Mm-Fe were prepared on AZ91 Mg-based alloys by high velocity arc spraying technique(HVAS).The structure character of the coatings indicates that coatings contain the mixture of amorphous phases and crystalline and there are both less than 2%porosity.The electrochemical tests of the coatings and the substrate were studied.The coatings show the passivation ability during polarization,but AZ91 Mg-based alloys show little passivation.The corrosion current density of the coatings is lower than that of AZ91 Mg-based alloys.The results show that the coatings have an excellent corrosion resistance for AZ91 Mg-based alloys in 5 wt%NaCl solution.展开更多
A FeCrSiBMn amorphous/nanocrystalline coating with 700 μm in thickness and 0.65% in porosity, was prepared by high velocity oxygen fuel(HVOF) spraying process. The long-term corrosion behavior of the FeCrSiBMn coatin...A FeCrSiBMn amorphous/nanocrystalline coating with 700 μm in thickness and 0.65% in porosity, was prepared by high velocity oxygen fuel(HVOF) spraying process. The long-term corrosion behavior of the FeCrSiBMn coating was evaluated by potentiodynamic polarization and electrochemical impedance spectroscopy(EIS) tests in a 3.5% NaCl solution with a hard chromium coating as a reference. The FeCrSiBMn coating exhibited higher corrosion potential and lower corrosion current density than the hard chromium coating. The pore resistance(Rp) and charge transfer resistance(Rct) of FeCrSiBMn coating were higher than those of the hard chromium coating. In addition, after immersion in the Na Cl solution for 28 d, only small pores in the FeCrSiBMn coating were observed. All the results indicated that the FeCrSiBMn coating held superior corrosion resistance to the hard chromium coating. This could be attributed to the dense structure, low porosity and amorphous/nanocrystalline phases of the FeCrSiBMn coating.展开更多
采用熔体快淬法制备了Fe_(80.8)Si_(7.2)B_6Nb_5Cu非晶条带,然后经过退火、研磨、成型、退火等一系列的处理,得到了结构致密的非晶纳米晶双相磁粉芯。研究了不同条件下磁粉芯的微观形貌、磁导率、功率损耗、品质因数等基本性能。研究结...采用熔体快淬法制备了Fe_(80.8)Si_(7.2)B_6Nb_5Cu非晶条带,然后经过退火、研磨、成型、退火等一系列的处理,得到了结构致密的非晶纳米晶双相磁粉芯。研究了不同条件下磁粉芯的微观形貌、磁导率、功率损耗、品质因数等基本性能。研究结果表明:Fe_(80.8)Si_(7.2)B_6Nb_5Cu非晶纳米晶双相磁粉芯具有较高磁导率(36~37),且在不同的频率和磁场下比较稳定;低频下(小于200 kHz),当磁场小于50 m T时,其功率损耗最大值仅为49.42 W/kg;同时,有着较好的品质因数。展开更多
Mg-based alloys are regarded as highly promising materials for hydrogen storage.Despite significant improvements of the properties for Mg-based alloys,challenges such as slow hydrogen absorption/desorption kinetics an...Mg-based alloys are regarded as highly promising materials for hydrogen storage.Despite significant improvements of the properties for Mg-based alloys,challenges such as slow hydrogen absorption/desorption kinetics and high thermodynamic stability continue to limit their practical application.In this study,to assess hydrogen storage alloys with enhanced properties,incorporating both internal microstructure modulation through the preparation of amorphous/nanocrystalline structures and surface property enhancement with the addition of Cu and carbon nanotubes(CNTs),the kinetic properties of activation and hydrogenation,thermodynamic properties,and dehydrogenation kinetics are tested.The results reveal a complementary interaction between the added Cu and CNTs,contributing to the superior hydrogen storage performance observed in sample 7A-2Cu-1CNTs with an amorphous/nanocrystalline structure compared to the other experimental samples.Additionally,the samples are fully activated after the initial hydrogen absorption and desorption cycle,demonstrating outstanding hydrogenation kinetics under both high and low temperature experimental conditions.Particularly noteworthy is that the hydrogen absorption exceeds 1.8 wt.% within one hour at 333 K.Furthermore,the activation energy for dehydrogenation is decreased to 64.71 kJ·mol^(–1).This research may offer novel insights for the design of new-type Mg-based hydrogen storage alloys,which possess milder conditions for hydrogen absorption and desorption.展开更多
基金National Natural Science Foundation of China(50905185)National"863"project of China(2009AA03Z342)
文摘The Al-based amorphous and nanocrystalline composite coatings with the composition of Al-Ni-Y-Co and Al-Ni-Mm-Fe were prepared on AZ91 Mg-based alloys by high velocity arc spraying technique(HVAS).The structure character of the coatings indicates that coatings contain the mixture of amorphous phases and crystalline and there are both less than 2%porosity.The electrochemical tests of the coatings and the substrate were studied.The coatings show the passivation ability during polarization,but AZ91 Mg-based alloys show little passivation.The corrosion current density of the coatings is lower than that of AZ91 Mg-based alloys.The results show that the coatings have an excellent corrosion resistance for AZ91 Mg-based alloys in 5 wt%NaCl solution.
文摘A FeCrSiBMn amorphous/nanocrystalline coating with 700 μm in thickness and 0.65% in porosity, was prepared by high velocity oxygen fuel(HVOF) spraying process. The long-term corrosion behavior of the FeCrSiBMn coating was evaluated by potentiodynamic polarization and electrochemical impedance spectroscopy(EIS) tests in a 3.5% NaCl solution with a hard chromium coating as a reference. The FeCrSiBMn coating exhibited higher corrosion potential and lower corrosion current density than the hard chromium coating. The pore resistance(Rp) and charge transfer resistance(Rct) of FeCrSiBMn coating were higher than those of the hard chromium coating. In addition, after immersion in the Na Cl solution for 28 d, only small pores in the FeCrSiBMn coating were observed. All the results indicated that the FeCrSiBMn coating held superior corrosion resistance to the hard chromium coating. This could be attributed to the dense structure, low porosity and amorphous/nanocrystalline phases of the FeCrSiBMn coating.
文摘采用熔体快淬法制备了Fe_(80.8)Si_(7.2)B_6Nb_5Cu非晶条带,然后经过退火、研磨、成型、退火等一系列的处理,得到了结构致密的非晶纳米晶双相磁粉芯。研究了不同条件下磁粉芯的微观形貌、磁导率、功率损耗、品质因数等基本性能。研究结果表明:Fe_(80.8)Si_(7.2)B_6Nb_5Cu非晶纳米晶双相磁粉芯具有较高磁导率(36~37),且在不同的频率和磁场下比较稳定;低频下(小于200 kHz),当磁场小于50 m T时,其功率损耗最大值仅为49.42 W/kg;同时,有着较好的品质因数。
基金funded by the National Key R&D Program of China(No.2021YFB4000604)the National Natural Science Foundations of China(No.52261041)+3 种基金Key R&D projects of Jilin Provincial Science and Technology Development Plan(No.20230201125GX)Youth Growth Science and Technology Program of Jilin Province(No.20220508001RC)Youth Innovation Promotion Association CAS(No.2022225)Independent Research Project of the State Key Laboratory of Rare Earth Resources Utilization,and Changchun Institute of Applied Chemistry,Chinese Academy of Sciences(No.110000RL86).
文摘Mg-based alloys are regarded as highly promising materials for hydrogen storage.Despite significant improvements of the properties for Mg-based alloys,challenges such as slow hydrogen absorption/desorption kinetics and high thermodynamic stability continue to limit their practical application.In this study,to assess hydrogen storage alloys with enhanced properties,incorporating both internal microstructure modulation through the preparation of amorphous/nanocrystalline structures and surface property enhancement with the addition of Cu and carbon nanotubes(CNTs),the kinetic properties of activation and hydrogenation,thermodynamic properties,and dehydrogenation kinetics are tested.The results reveal a complementary interaction between the added Cu and CNTs,contributing to the superior hydrogen storage performance observed in sample 7A-2Cu-1CNTs with an amorphous/nanocrystalline structure compared to the other experimental samples.Additionally,the samples are fully activated after the initial hydrogen absorption and desorption cycle,demonstrating outstanding hydrogenation kinetics under both high and low temperature experimental conditions.Particularly noteworthy is that the hydrogen absorption exceeds 1.8 wt.% within one hour at 333 K.Furthermore,the activation energy for dehydrogenation is decreased to 64.71 kJ·mol^(–1).This research may offer novel insights for the design of new-type Mg-based hydrogen storage alloys,which possess milder conditions for hydrogen absorption and desorption.
基金financially supported by Guangdong Major Project of Basic and Applied Basic Research,China (Grant No.2019B030302010)the National Natural Science Foundation of China (No.52301212,52071157,52071222)+1 种基金the National Key Research and Development Program of China (Grant No.2021YFA0716302)the open research fund of Songshan Lake Materials Laboratory (No.2022SLABFN11)。
