The Experts below are selected from a list of 29226 Experts worldwide ranked by ideXlab platform
Xingbo Liu - One of the best experts on this subject based on the ideXlab platform.
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corrosion fatigue crack growth behavior of oil grade nickel Base Alloy 718 part 1 effect of corrosive environment
Corrosion Science, 2014Co-Authors: Ting Chen, Jared S Nutter, Jeffrey A Hawk, Xingbo LiuAbstract:Abstract The effect of corrosive environment on corrosion fatigue crack growth (CFCG) behavior of oil-grade nickel-Base Alloy 718 is studied. The results demonstrate that there is no obvious effect of 3.5 wt.% NaCl solution at RT, 50 °C and 80 °C on CGCG rates while 21 wt.% NaCl solution at 80 °C produces a deleterious effect on CFCG rates compared to the ones tested in air. Potentiodynamic polarization results show that Alloy 718 exhibits passive behavior in 3.5 wt.% NaCl solution, while pitting corrosion resistance decreases with increasing solution temperature. Nevertheless, Alloy 718 shows active corrosion behavior in 21 wt.% NaCl solution at 80 °C.
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influence of surface modifications on pitting corrosion behavior of nickel Base Alloy 718 part 1 effect of machine hammer peening
Corrosion Science, 2013Co-Authors: Ting Chen, Jeffrey A Hawk, Hendrik John, Xingbo LiuAbstract:Abstract The effect of surface modifications induced by machine hammer peening on pitting corrosion behavior of nickel-Base Alloy 718 in a 3.5 wt.% NaCl solution is investigated. Severe work hardening and high compressive residual stress are generated with surface smoothing and microstructure evolution in terms of formation of nano-grains and nano-twins in the near surface region after machine hammer peening. Electrochemical tests results show that machine hammer peening has a beneficial influence on the corrosion resistance, indicated by a significant increase of the critical pitting potential (+134 mV) accompanied with lower corrosion current density and higher polarization resistance.
Ting Chen - One of the best experts on this subject based on the ideXlab platform.
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corrosion fatigue crack growth behavior of oil grade nickel Base Alloy 718 part 1 effect of corrosive environment
Corrosion Science, 2014Co-Authors: Ting Chen, Jared S Nutter, Jeffrey A Hawk, Xingbo LiuAbstract:Abstract The effect of corrosive environment on corrosion fatigue crack growth (CFCG) behavior of oil-grade nickel-Base Alloy 718 is studied. The results demonstrate that there is no obvious effect of 3.5 wt.% NaCl solution at RT, 50 °C and 80 °C on CGCG rates while 21 wt.% NaCl solution at 80 °C produces a deleterious effect on CFCG rates compared to the ones tested in air. Potentiodynamic polarization results show that Alloy 718 exhibits passive behavior in 3.5 wt.% NaCl solution, while pitting corrosion resistance decreases with increasing solution temperature. Nevertheless, Alloy 718 shows active corrosion behavior in 21 wt.% NaCl solution at 80 °C.
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influence of surface modifications on pitting corrosion behavior of nickel Base Alloy 718 part 1 effect of machine hammer peening
Corrosion Science, 2013Co-Authors: Ting Chen, Jeffrey A Hawk, Hendrik John, Xingbo LiuAbstract:Abstract The effect of surface modifications induced by machine hammer peening on pitting corrosion behavior of nickel-Base Alloy 718 in a 3.5 wt.% NaCl solution is investigated. Severe work hardening and high compressive residual stress are generated with surface smoothing and microstructure evolution in terms of formation of nano-grains and nano-twins in the near surface region after machine hammer peening. Electrochemical tests results show that machine hammer peening has a beneficial influence on the corrosion resistance, indicated by a significant increase of the critical pitting potential (+134 mV) accompanied with lower corrosion current density and higher polarization resistance.
Il Soon Hwang - One of the best experts on this subject based on the ideXlab platform.
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in situ investigation of thermal aging effect on oxide formation in ni Base Alloy low Alloy steel dissimilar metal weld interfaces
Corrosion Science, 2014Co-Authors: Kyung Joon Choi, Chi Bum Bahn, Il Soon HwangAbstract:Abstract The thermal aging effect on the formation of oxide films at the interfaces of nickel-Base Alloy/low Alloy steel dissimilar metal welds has been analyzed by in-situ Raman spectroscopy. Experimental conditions were controlled so as to simulate a pressurized water reactor primary water condition, with in-situ spectra recorded at 300 °C for 50 h. The results indicate the formation of Cr 2 O 3 , Fe 3 O 4 , and FeCr 2 O 3 in as-welded samples, whereas thermal aging is found to form NiCr 2 O 4 and NiFe 2 O 4 . In this study, therefore, it is determined that the thermal aging creates a susceptibility to stress corrosion cracking that is not present in the as-welded sample.
Kyung Joon Choi - One of the best experts on this subject based on the ideXlab platform.
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in situ investigation of thermal aging effect on oxide formation in ni Base Alloy low Alloy steel dissimilar metal weld interfaces
Corrosion Science, 2014Co-Authors: Kyung Joon Choi, Chi Bum Bahn, Il Soon HwangAbstract:Abstract The thermal aging effect on the formation of oxide films at the interfaces of nickel-Base Alloy/low Alloy steel dissimilar metal welds has been analyzed by in-situ Raman spectroscopy. Experimental conditions were controlled so as to simulate a pressurized water reactor primary water condition, with in-situ spectra recorded at 300 °C for 50 h. The results indicate the formation of Cr 2 O 3 , Fe 3 O 4 , and FeCr 2 O 3 in as-welded samples, whereas thermal aging is found to form NiCr 2 O 4 and NiFe 2 O 4 . In this study, therefore, it is determined that the thermal aging creates a susceptibility to stress corrosion cracking that is not present in the as-welded sample.
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in situ raman spectroscopic analysis of surface oxide films on ni Base Alloy low Alloy steel dissimilar metal weld interfaces in high temperature water
Journal of Nuclear Materials, 2014Co-Authors: Kyung Joon Choi, Chi Bum BahnAbstract:Abstract In situ Raman spectroscopy has been applied to analyze the surface oxide films formed on dissimilar metal weld (DMW) interfaces of nickel-Base Alloy/low Alloy steel under hydrogenated high-temperature water condition. For the analysis of the oxide films under high temperature/pressure aqueous conditions, an in situ Raman spectroscopy system was developed by constructing a hydrothermal cell where the entire optics including the excitation laser and the Raman light collection system were located at the nearest position to the specimen by means of immersion optics. In situ Raman spectra of the DMW interfaces were collected in hydrogenated water condition at different temperatures up to 300 °C. The measured in situ Raman spectra showed peaks of Cr 2 O 3 , NiCr 2 O 4 and Fe 3 O 4 at the DMW interface. It is considered that differences in the oxide chemistry originated from the chemical element distribution inside of the DMW interface region.
Jeffrey A Hawk - One of the best experts on this subject based on the ideXlab platform.
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corrosion fatigue crack growth behavior of oil grade nickel Base Alloy 718 part 1 effect of corrosive environment
Corrosion Science, 2014Co-Authors: Ting Chen, Jared S Nutter, Jeffrey A Hawk, Xingbo LiuAbstract:Abstract The effect of corrosive environment on corrosion fatigue crack growth (CFCG) behavior of oil-grade nickel-Base Alloy 718 is studied. The results demonstrate that there is no obvious effect of 3.5 wt.% NaCl solution at RT, 50 °C and 80 °C on CGCG rates while 21 wt.% NaCl solution at 80 °C produces a deleterious effect on CFCG rates compared to the ones tested in air. Potentiodynamic polarization results show that Alloy 718 exhibits passive behavior in 3.5 wt.% NaCl solution, while pitting corrosion resistance decreases with increasing solution temperature. Nevertheless, Alloy 718 shows active corrosion behavior in 21 wt.% NaCl solution at 80 °C.
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influence of surface modifications on pitting corrosion behavior of nickel Base Alloy 718 part 1 effect of machine hammer peening
Corrosion Science, 2013Co-Authors: Ting Chen, Jeffrey A Hawk, Hendrik John, Xingbo LiuAbstract:Abstract The effect of surface modifications induced by machine hammer peening on pitting corrosion behavior of nickel-Base Alloy 718 in a 3.5 wt.% NaCl solution is investigated. Severe work hardening and high compressive residual stress are generated with surface smoothing and microstructure evolution in terms of formation of nano-grains and nano-twins in the near surface region after machine hammer peening. Electrochemical tests results show that machine hammer peening has a beneficial influence on the corrosion resistance, indicated by a significant increase of the critical pitting potential (+134 mV) accompanied with lower corrosion current density and higher polarization resistance.
