In this study,pure Ni was demonstrated to protect the GH3535 alloy from Te vapor corrosion because of its strong absorption capacity.Severe Te corrosion of a single GH3535 alloy sample occurred in Te vapor at 700C,whi...In this study,pure Ni was demonstrated to protect the GH3535 alloy from Te vapor corrosion because of its strong absorption capacity.Severe Te corrosion of a single GH3535 alloy sample occurred in Te vapor at 700C,which manifested as complex surface corrosion products and deep intergranular cracks.However,when pure Ni and the GH3535 alloy were put together in the vessel,the GH3535 alloy was completely protected from Te corrosion at the expense of the pure Ni.Thermodynamic calculations proved that the preferential reaction between pure Ni and Te vapor reduced the activity of Te vapor considerably,preventing the corrosion of the GH3535 alloy.Our study reveals one potential approach for protecting the alloys used in molten-salt reactors from Te corrosion.展开更多
Corrosion behavior of a Ni-16Mo-7Cr base superalloy was systematically investigated under a selenium(Se)atmosphere at 700°C.It shows that Se can react with the alloy elements such as Ni,Mo,Cr et al.to form a reac...Corrosion behavior of a Ni-16Mo-7Cr base superalloy was systematically investigated under a selenium(Se)atmosphere at 700°C.It shows that Se can react with the alloy elements such as Ni,Mo,Cr et al.to form a reaction layer at the surface of alloy,which is mainly composed of Ni_(2)Se_(3),MoSe_(2),and Cr_(3)Se_(4).The tensile properties of the alloy are not greatly affected by changes of Se content.The slight decrease in the tensile strength is attributed to the formation of the reaction layer,which leads to the decrease in the effective undertaking area of the alloy.No intergranular diffusion characteristic of Se elements was observed,and the Se effect of embrittlement on grain boundaries is weaker than that of tellurium(Te).展开更多
The GH3535 alloy samples were irradiated using 15-MeV Te^(4+) ions at 650℃to a dose of 0.5,3.0,10,and 20 dpa,respectively.The Te atoms distribution and microstructure evolution were examined by electron probe microan...The GH3535 alloy samples were irradiated using 15-MeV Te^(4+) ions at 650℃to a dose of 0.5,3.0,10,and 20 dpa,respectively.The Te atoms distribution and microstructure evolution were examined by electron probe microanalysis(EPMA)and transmission electron microscopy(TEM).The nano-indenter was then used to measure the nano-hardness changes of samples before and after irradiation.TEM results showed the formation of dislocation loops in the irradiated samples.Their mean diameters increase with the increase of irradiation dose and tends to be saturated when irradiation dose exceeds 10 dpa.The ratio of yield strength increments calculated by dispersed barrier hardening(DBH)model is basically consistent with that of nano-hardness increments measured by nano-indenter.In addition,the relationship between the nano-hardness increments and dpa for the GH3535 alloy irradiated by Te ions has been revealed in the study.展开更多
基金the National Natural Science Foundation of China(Nos.U2032205,52171023,51971238,and 52005492)Natural Science Foundation of Shanghai(Nos.20ZR1468600 and 19ZR1468200)+1 种基金Shanghai Sailing Program(No.19YF1458300)the Youth Innovation Promotion Association,Chinese Academy of Science(No.2019264)。
文摘In this study,pure Ni was demonstrated to protect the GH3535 alloy from Te vapor corrosion because of its strong absorption capacity.Severe Te corrosion of a single GH3535 alloy sample occurred in Te vapor at 700C,which manifested as complex surface corrosion products and deep intergranular cracks.However,when pure Ni and the GH3535 alloy were put together in the vessel,the GH3535 alloy was completely protected from Te corrosion at the expense of the pure Ni.Thermodynamic calculations proved that the preferential reaction between pure Ni and Te vapor reduced the activity of Te vapor considerably,preventing the corrosion of the GH3535 alloy.Our study reveals one potential approach for protecting the alloys used in molten-salt reactors from Te corrosion.
基金This work was financially supported by the National Natural Science Foundation of China(Grant Nos.52071331,51901241,52001322).
文摘Corrosion behavior of a Ni-16Mo-7Cr base superalloy was systematically investigated under a selenium(Se)atmosphere at 700°C.It shows that Se can react with the alloy elements such as Ni,Mo,Cr et al.to form a reaction layer at the surface of alloy,which is mainly composed of Ni_(2)Se_(3),MoSe_(2),and Cr_(3)Se_(4).The tensile properties of the alloy are not greatly affected by changes of Se content.The slight decrease in the tensile strength is attributed to the formation of the reaction layer,which leads to the decrease in the effective undertaking area of the alloy.No intergranular diffusion characteristic of Se elements was observed,and the Se effect of embrittlement on grain boundaries is weaker than that of tellurium(Te).
基金the National Natural Science Foundation of China(Grant Nos.11975304 and 12022515).
文摘The GH3535 alloy samples were irradiated using 15-MeV Te^(4+) ions at 650℃to a dose of 0.5,3.0,10,and 20 dpa,respectively.The Te atoms distribution and microstructure evolution were examined by electron probe microanalysis(EPMA)and transmission electron microscopy(TEM).The nano-indenter was then used to measure the nano-hardness changes of samples before and after irradiation.TEM results showed the formation of dislocation loops in the irradiated samples.Their mean diameters increase with the increase of irradiation dose and tends to be saturated when irradiation dose exceeds 10 dpa.The ratio of yield strength increments calculated by dispersed barrier hardening(DBH)model is basically consistent with that of nano-hardness increments measured by nano-indenter.In addition,the relationship between the nano-hardness increments and dpa for the GH3535 alloy irradiated by Te ions has been revealed in the study.
