The effects of hydrogen charging time and pressure on the hydrogen embrittlement(HE)susceptibility of X52 pipeline steel material are studied by slow strain rate tensile tests.The fracture morphologies of the specimen...The effects of hydrogen charging time and pressure on the hydrogen embrittlement(HE)susceptibility of X52 pipeline steel material are studied by slow strain rate tensile tests.The fracture morphologies of the specimens are observed by scanning electron microscopy.The HE susceptibility of the X52 pipeline steel material increases with an increase in both hydrogen charging time and hydrogen pressure.At a charging time of 96 h,the HE susceptibility index reaches 45.86%,approximately 3.6 times that at a charging time of 0 h.Similarly,a charging pressure of 4 MPa results in a HE susceptibility index of 31.61%,approximately 2.5 times higher than that at a charging pressure of 0.3 MPa.展开更多
The hydrogen distribution curve along cross-section of high pressure hydrogen charged spec- imens of 21Cr-7Ni-9Mn-N austenitic steel was obtained quantitatively by IMMA(Ion Microprobe Mass Analyzer).Thus the hydrogen ...The hydrogen distribution curve along cross-section of high pressure hydrogen charged spec- imens of 21Cr-7Ni-9Mn-N austenitic steel was obtained quantitatively by IMMA(Ion Microprobe Mass Analyzer).Thus the hydrogen solubility and diffusivity may be measured, and the hydrogen permeability and other parameters may be calculated indirectly.The hydrogen distribution in specimens either long-term aged in air or in electron beam weld seam after high pressure hydrogen charging was also examined.展开更多
The charge transport behavior of barium fluoride nanocrystals is investigated by in situ impedance measurement up to 35 GPa. It is found that the parameters change discontinuously at about 6.9 GPa, corresponding to th...The charge transport behavior of barium fluoride nanocrystals is investigated by in situ impedance measurement up to 35 GPa. It is found that the parameters change discontinuously at about 6.9 GPa, corresponding to the phase transition of BaF2 nanocrystals under high pressure. The charge carriers in BaF2 nanocrystals include both Fions and electrons. Pressure makes the electronic transport more difficult. The defects at grains dominate the electronic transport process. Pressure could make the charge-discharge processes in the Fm3m phase more difficult.展开更多
基金This work was supported by the National Key R&D Program of China(2021YFB4001601)the Youth Innovation Promotion Association CAS(2022187).
文摘The effects of hydrogen charging time and pressure on the hydrogen embrittlement(HE)susceptibility of X52 pipeline steel material are studied by slow strain rate tensile tests.The fracture morphologies of the specimens are observed by scanning electron microscopy.The HE susceptibility of the X52 pipeline steel material increases with an increase in both hydrogen charging time and hydrogen pressure.At a charging time of 96 h,the HE susceptibility index reaches 45.86%,approximately 3.6 times that at a charging time of 0 h.Similarly,a charging pressure of 4 MPa results in a HE susceptibility index of 31.61%,approximately 2.5 times higher than that at a charging pressure of 0.3 MPa.
文摘The hydrogen distribution curve along cross-section of high pressure hydrogen charged spec- imens of 21Cr-7Ni-9Mn-N austenitic steel was obtained quantitatively by IMMA(Ion Microprobe Mass Analyzer).Thus the hydrogen solubility and diffusivity may be measured, and the hydrogen permeability and other parameters may be calculated indirectly.The hydrogen distribution in specimens either long-term aged in air or in electron beam weld seam after high pressure hydrogen charging was also examined.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11374131,11674404,11404137 and 61378085the Program for New Century Excellent Talents in University under Grant No NCET-13-0824+1 种基金the Program for the Development of Science and Technology of Jilin Province under Grant Nos 201201079 and 20150204085GXthe Twentieth Five-Year Program for Science and Technology of Education Department of Jilin Province under Grant No 20150221
文摘The charge transport behavior of barium fluoride nanocrystals is investigated by in situ impedance measurement up to 35 GPa. It is found that the parameters change discontinuously at about 6.9 GPa, corresponding to the phase transition of BaF2 nanocrystals under high pressure. The charge carriers in BaF2 nanocrystals include both Fions and electrons. Pressure makes the electronic transport more difficult. The defects at grains dominate the electronic transport process. Pressure could make the charge-discharge processes in the Fm3m phase more difficult.
