The Experts below are selected from a list of 297 Experts worldwide ranked by ideXlab platform
Guojun Yu - One of the best experts on this subject based on the ideXlab platform.
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effect of crf 3 on the corrosion behaviour of Hastelloy n and 316l stainless steel alloys in flinak molten salt
Corrosion Science, 2018Co-Authors: Yang Wang, Sufang Zhao, Xuehui An, Jinhui Cheng, Tao Chen, Peng Zhang, Guojun YuAbstract:Abstract The effect of CrF3 on the corrosion behaviour of Hastelloy-N and 316L austenitic stainless steel alloys in FLiNaK at 700 °C was investigated using synchrotron radiation and other characterisation techniques. The results showed that CrF3 considerably accelerated the corrosion of both tested alloys by promoting the dissolution of Cr, Fe, and Mn from alloy matrices into molten salt. The 316L stainless steel alloys mainly exhibited intergranular corrosion, whereas the Hastelloy-N alloys tended to exhibit intergranular and pitting corrosion. After corrosion, the lattice parameter of both alloys decreased and Cr1.07Fe18.93 was formed on the surface of the 316L stainless steel alloys.
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corrosion of sic induced by Hastelloy n alloy and its corrosion products in lif naf kf molten salt
Corrosion Science, 2016Co-Authors: Xinmei Yang, Zhijun Li, Guojun Yu, Dongsheng Zhang, Shanglei Feng, Xingtai Zhou, Ping Huai, Yanling Lu, Haijun Zhou, Shaoming DongAbstract:Abstract Interaction between SiC and Hastelloy N alloy in LiF–NaF–KF salt was studied for the application of SiC to molten salt reactors. Results reveal that Hastelloy N alloy and its corrosion products can induce the corrosion of SiC in salt. Ni can react with Si in salt to form silicide (Ni31Si12, NiSi). Cr2+ can react with SiC to form carbide (Cr7C3, CrC). Ni2+ can cause SiC with a thickness of 50 μm almost disappear after 45 days; thus, the Si content in salt can increase to 0.5 wt%. Raman spectrum indicates that Si in salt is in the form of [SiF6]2−.
Majid Etminanbakhsh - One of the best experts on this subject based on the ideXlab platform.
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microstructural evolution and interfacial diffusion during heat treatment of Hastelloy stainless steel bimetals
Journal of Alloys and Compounds, 2017Co-Authors: O Hedayati, N Korei, M Adeli, Majid EtminanbakhshAbstract:Abstract Hastelloy/stainless steel bimetals have found wide applications in chemical, petrochemical, and marine applications. In this study, the effect of short-time exposure to elevated temperatures on an explosively-welded Hastelloy/stainless steel bimetal was investigated. Samples prepared from the bimetal were heat-treated at 800 °C, 900 °C, 1000 °C, and 1100 °C for times up to 3 h. Microscopic examination of the interface showed no variations in the microstructure after heating at 800 °C even at longer times. At 900 °C and 1000 °C, the interdiffusion of atoms became significant; arrays of carbide precipitates appeared in the microstructure on the Hastelloy side which seemed to coarsen with increase in temperature and time. At temperatures as high as 1100 °C, 30min of heat treatment resulted in the formation of a significant number of coarse carbide precipitates on the Hastelloy side, as well as a line of carbides on the steel side. It was concluded that these bimetals may not be suitable for application in service temperatures higher than 800 °C. Even short-time exposure to elevated temperatures can develop coarse carbide networks at the interface, rendering the weld unreliable and susceptible to failure.
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Microstructural evolution and interfacial diffusion during heat treatment of Hastelloy/stainless steel bimetals
Journal of Alloys and Compounds, 2017Co-Authors: O Hedayati, N Korei, M Adeli, Majid EtminanbakhshAbstract:Abstract Hastelloy/stainless steel bimetals have found wide applications in chemical, petrochemical, and marine applications. In this study, the effect of short-time exposure to elevated temperatures on an explosively-welded Hastelloy/stainless steel bimetal was investigated. Samples prepared from the bimetal were heat-treated at 800 °C, 900 °C, 1000 °C, and 1100 °C for times up to 3 h. Microscopic examination of the interface showed no variations in the microstructure after heating at 800 °C even at longer times. At 900 °C and 1000 °C, the interdiffusion of atoms became significant; arrays of carbide precipitates appeared in the microstructure on the Hastelloy side which seemed to coarsen with increase in temperature and time. At temperatures as high as 1100 °C, 30min of heat treatment resulted in the formation of a significant number of coarse carbide precipitates on the Hastelloy side, as well as a line of carbides on the steel side. It was concluded that these bimetals may not be suitable for application in service temperatures higher than 800 °C. Even short-time exposure to elevated temperatures can develop coarse carbide networks at the interface, rendering the weld unreliable and susceptible to failure.
Zhengren Huang - One of the best experts on this subject based on the ideXlab platform.
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oxidation resistance optimization of tic Hastelloy composites by adding ta element applied for intermediate temperature solid oxide fuel cell interconnects
Journal of Power Sources, 2018Co-Authors: Qian Qi, Lujie Wang, Zhengren HuangAbstract:Abstract Excellent oxidation resistance is one crucial requirement for intermediate-temperature solid oxide fuel cell interconnects. Composites with proper coefficient of thermal expansion and good electrical conductivity have been proposed as promising intermediate-temperature solid oxide fuel cell interconnects, whereas the oxidation resistance of them is still need to be improved. In the paper, the TiC/Hastelloy composites with minor Ta element are prepared by in-situ reactive infiltration method, and the mass gain decreases from 1.18 mg cm−2 to 0.48 mg cm−2 (800 °C/100 h) by adding minor Ta, which is the lowest among existing composite interconnects. The oxide scale composed of Ni/Ti/Cr oxides with sandwich structure is formed on the composites. Compared with TiC/Hastelloy composites without Ta element, Ta effectively prevents the inward diffusion of oxygen during oxidation by reducing oxygen vacancy concentration in TiO2 layer, and the inner oxide layer (O diffusion layer) vanishes, leading to the oxidation resistance optimization of composites. Meanwhile, the composites with Ta show linear suitable thermal expansion, 11.6 × 10−6 °C−1, and high electrical conductivity, 5500 S cm−1. Therefore, the addition of minor Ta element is one effective method to optimize the oxidation resistance of TiC/Hastelloy composites.
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interfacial effect on oxidation resistance of tic Hastelloy composites applied for intermediate temperature solid oxide fuel cell interconnects
Corrosion Science, 2018Co-Authors: Qian Qi, Lujie Wang, Zhengren HuangAbstract:Abstract Better interfacial bonding with fewer dislocations is observed between in-situ TiC and Hastelloy than that between ex-situ TiC and Hastelloy, which slows down the diffusion rate of Ti and O during oxidation process. Mass gain (800 °C/100 h) of in-situ TiC/Hastelloy composites is 2.60 mg cm−2 with oxidation rate 6.84 × 10−8 g2 cm−4 h−1, much lower than 4.17 mg cm−2 with oxidation rate of 1.75 × 10−7 g2 cm−4 h−1 of ex-situ TiC/Hastelloy composites. Besides, smaller TiO2 area is formed on in-situ TiC/Hastelloy composites with smaller interparticle spacing of TiC, against the prediction that the decrease of interparticle spacing of TiC accelerates the formation of continuous TiO2 area.
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Interfacial effect on oxidation resistance of TiC/Hastelloy composites applied for intermediate-temperature solid oxide fuel cell interconnects
Corrosion Science, 2018Co-Authors: Qian Qi, Lujie Wang, Zhengren HuangAbstract:Abstract Better interfacial bonding with fewer dislocations is observed between in-situ TiC and Hastelloy than that between ex-situ TiC and Hastelloy, which slows down the diffusion rate of Ti and O during oxidation process. Mass gain (800 °C/100 h) of in-situ TiC/Hastelloy composites is 2.60 mg cm−2 with oxidation rate 6.84 × 10−8 g2 cm−4 h−1, much lower than 4.17 mg cm−2 with oxidation rate of 1.75 × 10−7 g2 cm−4 h−1 of ex-situ TiC/Hastelloy composites. Besides, smaller TiO2 area is formed on in-situ TiC/Hastelloy composites with smaller interparticle spacing of TiC, against the prediction that the decrease of interparticle spacing of TiC accelerates the formation of continuous TiO2 area.
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the oxidation resistance optimization of titanium carbide Hastelloy ni based alloy composites applied for intermediate temperature solid oxide fuel cell interconnects
Journal of Power Sources, 2017Co-Authors: Qian Qi, Lujie Wang, Jian Huang, Zhengren HuangAbstract:Abstract Titanium carbide/Hastelloy (TiC/Hastelloy) composites are potential candidates for intermediate-temperature solid oxide fuel cell interconnects. In this work, TiC/Hastelloy composites with suitable coefficient of thermal expansion are fabricated by in-situ reactive infiltration method, and their properties are optimized by adjusting TiC particle size (d TiC ). The oxidation process of TiC/Hastelloy composites is comprehensive performance of TiC and Ni-Cr alloy and determined by outward diffusion of Ti and Ni atoms and internal diffusion of O 2 . The oxidation resistance of composites could be improved by the decrease of d TiC through accelerating the formation of continuous and dense TiO 2 /Cr 2 O 3 oxide scale. Moreover, the electrical conductivity of composites at 800 °C for 100 h is 5600–7500 S cm −1 and changes little with the prolongation of oxidation time. The decrease of d TiC is favorable for the properties optimization, and composites with 2.16 μm TiC exhibits good integrated properties.
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processing and microstructure characterization of sicp Hastelloy ni mo cr composites prepared by pressureless infiltration
Journal of Alloys and Compounds, 2015Co-Authors: Qian Qi, Hui Zhang, Yinsheng Li, Hanqin Liang, Zhengren HuangAbstract:Abstract SiC p /Hastelloy composites were fabricated by pressureless Ti-activated infiltration process. The wetting and infiltration behaviors of Hastelloy on the SiC substrates and the interfacial reaction between the SiC particles and Hastelloy were investigated by real-time observation system, X-ray diffraction (XRD) and scanning electron microscopy (SEM) equipped with energy X-ray dispersive spectroscopy (EDS) system. The results demonstrated that the Hastelloy had a good wettability on SiC ceramic and could spontaneously infiltrate into the Ti-activated SiC preform. Moreover, intensive interfacial reaction similar to SiC/Ni system was found between the SiC particles and Hastelloy, which induced defects in the microstructure. In order to inhibit the interfacial reaction, Al 2 O 3 coating on SiC particles was adopted as a diffusion barrier, which effectively reduced the extent of the interfacial reactions.
Qian Qi - One of the best experts on this subject based on the ideXlab platform.
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oxidation resistance optimization of tic Hastelloy composites by adding ta element applied for intermediate temperature solid oxide fuel cell interconnects
Journal of Power Sources, 2018Co-Authors: Qian Qi, Lujie Wang, Zhengren HuangAbstract:Abstract Excellent oxidation resistance is one crucial requirement for intermediate-temperature solid oxide fuel cell interconnects. Composites with proper coefficient of thermal expansion and good electrical conductivity have been proposed as promising intermediate-temperature solid oxide fuel cell interconnects, whereas the oxidation resistance of them is still need to be improved. In the paper, the TiC/Hastelloy composites with minor Ta element are prepared by in-situ reactive infiltration method, and the mass gain decreases from 1.18 mg cm−2 to 0.48 mg cm−2 (800 °C/100 h) by adding minor Ta, which is the lowest among existing composite interconnects. The oxide scale composed of Ni/Ti/Cr oxides with sandwich structure is formed on the composites. Compared with TiC/Hastelloy composites without Ta element, Ta effectively prevents the inward diffusion of oxygen during oxidation by reducing oxygen vacancy concentration in TiO2 layer, and the inner oxide layer (O diffusion layer) vanishes, leading to the oxidation resistance optimization of composites. Meanwhile, the composites with Ta show linear suitable thermal expansion, 11.6 × 10−6 °C−1, and high electrical conductivity, 5500 S cm−1. Therefore, the addition of minor Ta element is one effective method to optimize the oxidation resistance of TiC/Hastelloy composites.
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interfacial effect on oxidation resistance of tic Hastelloy composites applied for intermediate temperature solid oxide fuel cell interconnects
Corrosion Science, 2018Co-Authors: Qian Qi, Lujie Wang, Zhengren HuangAbstract:Abstract Better interfacial bonding with fewer dislocations is observed between in-situ TiC and Hastelloy than that between ex-situ TiC and Hastelloy, which slows down the diffusion rate of Ti and O during oxidation process. Mass gain (800 °C/100 h) of in-situ TiC/Hastelloy composites is 2.60 mg cm−2 with oxidation rate 6.84 × 10−8 g2 cm−4 h−1, much lower than 4.17 mg cm−2 with oxidation rate of 1.75 × 10−7 g2 cm−4 h−1 of ex-situ TiC/Hastelloy composites. Besides, smaller TiO2 area is formed on in-situ TiC/Hastelloy composites with smaller interparticle spacing of TiC, against the prediction that the decrease of interparticle spacing of TiC accelerates the formation of continuous TiO2 area.
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Interfacial effect on oxidation resistance of TiC/Hastelloy composites applied for intermediate-temperature solid oxide fuel cell interconnects
Corrosion Science, 2018Co-Authors: Qian Qi, Lujie Wang, Zhengren HuangAbstract:Abstract Better interfacial bonding with fewer dislocations is observed between in-situ TiC and Hastelloy than that between ex-situ TiC and Hastelloy, which slows down the diffusion rate of Ti and O during oxidation process. Mass gain (800 °C/100 h) of in-situ TiC/Hastelloy composites is 2.60 mg cm−2 with oxidation rate 6.84 × 10−8 g2 cm−4 h−1, much lower than 4.17 mg cm−2 with oxidation rate of 1.75 × 10−7 g2 cm−4 h−1 of ex-situ TiC/Hastelloy composites. Besides, smaller TiO2 area is formed on in-situ TiC/Hastelloy composites with smaller interparticle spacing of TiC, against the prediction that the decrease of interparticle spacing of TiC accelerates the formation of continuous TiO2 area.
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the oxidation resistance optimization of titanium carbide Hastelloy ni based alloy composites applied for intermediate temperature solid oxide fuel cell interconnects
Journal of Power Sources, 2017Co-Authors: Qian Qi, Lujie Wang, Jian Huang, Zhengren HuangAbstract:Abstract Titanium carbide/Hastelloy (TiC/Hastelloy) composites are potential candidates for intermediate-temperature solid oxide fuel cell interconnects. In this work, TiC/Hastelloy composites with suitable coefficient of thermal expansion are fabricated by in-situ reactive infiltration method, and their properties are optimized by adjusting TiC particle size (d TiC ). The oxidation process of TiC/Hastelloy composites is comprehensive performance of TiC and Ni-Cr alloy and determined by outward diffusion of Ti and Ni atoms and internal diffusion of O 2 . The oxidation resistance of composites could be improved by the decrease of d TiC through accelerating the formation of continuous and dense TiO 2 /Cr 2 O 3 oxide scale. Moreover, the electrical conductivity of composites at 800 °C for 100 h is 5600–7500 S cm −1 and changes little with the prolongation of oxidation time. The decrease of d TiC is favorable for the properties optimization, and composites with 2.16 μm TiC exhibits good integrated properties.
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processing and microstructure characterization of sicp Hastelloy ni mo cr composites prepared by pressureless infiltration
Journal of Alloys and Compounds, 2015Co-Authors: Qian Qi, Hui Zhang, Yinsheng Li, Hanqin Liang, Zhengren HuangAbstract:Abstract SiC p /Hastelloy composites were fabricated by pressureless Ti-activated infiltration process. The wetting and infiltration behaviors of Hastelloy on the SiC substrates and the interfacial reaction between the SiC particles and Hastelloy were investigated by real-time observation system, X-ray diffraction (XRD) and scanning electron microscopy (SEM) equipped with energy X-ray dispersive spectroscopy (EDS) system. The results demonstrated that the Hastelloy had a good wettability on SiC ceramic and could spontaneously infiltrate into the Ti-activated SiC preform. Moreover, intensive interfacial reaction similar to SiC/Ni system was found between the SiC particles and Hastelloy, which induced defects in the microstructure. In order to inhibit the interfacial reaction, Al 2 O 3 coating on SiC particles was adopted as a diffusion barrier, which effectively reduced the extent of the interfacial reactions.
O Hedayati - One of the best experts on this subject based on the ideXlab platform.
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microstructural evolution and interfacial diffusion during heat treatment of Hastelloy stainless steel bimetals
Journal of Alloys and Compounds, 2017Co-Authors: O Hedayati, N Korei, M Adeli, Majid EtminanbakhshAbstract:Abstract Hastelloy/stainless steel bimetals have found wide applications in chemical, petrochemical, and marine applications. In this study, the effect of short-time exposure to elevated temperatures on an explosively-welded Hastelloy/stainless steel bimetal was investigated. Samples prepared from the bimetal were heat-treated at 800 °C, 900 °C, 1000 °C, and 1100 °C for times up to 3 h. Microscopic examination of the interface showed no variations in the microstructure after heating at 800 °C even at longer times. At 900 °C and 1000 °C, the interdiffusion of atoms became significant; arrays of carbide precipitates appeared in the microstructure on the Hastelloy side which seemed to coarsen with increase in temperature and time. At temperatures as high as 1100 °C, 30min of heat treatment resulted in the formation of a significant number of coarse carbide precipitates on the Hastelloy side, as well as a line of carbides on the steel side. It was concluded that these bimetals may not be suitable for application in service temperatures higher than 800 °C. Even short-time exposure to elevated temperatures can develop coarse carbide networks at the interface, rendering the weld unreliable and susceptible to failure.
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Microstructural evolution and interfacial diffusion during heat treatment of Hastelloy/stainless steel bimetals
Journal of Alloys and Compounds, 2017Co-Authors: O Hedayati, N Korei, M Adeli, Majid EtminanbakhshAbstract:Abstract Hastelloy/stainless steel bimetals have found wide applications in chemical, petrochemical, and marine applications. In this study, the effect of short-time exposure to elevated temperatures on an explosively-welded Hastelloy/stainless steel bimetal was investigated. Samples prepared from the bimetal were heat-treated at 800 °C, 900 °C, 1000 °C, and 1100 °C for times up to 3 h. Microscopic examination of the interface showed no variations in the microstructure after heating at 800 °C even at longer times. At 900 °C and 1000 °C, the interdiffusion of atoms became significant; arrays of carbide precipitates appeared in the microstructure on the Hastelloy side which seemed to coarsen with increase in temperature and time. At temperatures as high as 1100 °C, 30min of heat treatment resulted in the formation of a significant number of coarse carbide precipitates on the Hastelloy side, as well as a line of carbides on the steel side. It was concluded that these bimetals may not be suitable for application in service temperatures higher than 800 °C. Even short-time exposure to elevated temperatures can develop coarse carbide networks at the interface, rendering the weld unreliable and susceptible to failure.
