A systematic investigation was carried out to discuss the corrosion and tribocorrosion behaviors of Hastelloy C276 alloy sliding against Al2O3 pin in artificial seawater, using a pin-on-disk tribometer integrated with...A systematic investigation was carried out to discuss the corrosion and tribocorrosion behaviors of Hastelloy C276 alloy sliding against Al2O3 pin in artificial seawater, using a pin-on-disk tribometer integrated with a potentiostat for electrochemical control. The results show that the great decrease of open circuit potential and three orders of magnitude increase of corrosion current density occur caused by friction. There are clearly synergistic effect between corrosion and wear, resulting in corrosion-induced-wear and wear-induced-corrosion in tribocorrosion process. The contribution of pure mechanical wear to total material loss exceeds 70% in all sliding conditions, so mechanical wear is the dominant factor during tribocorrosion. For considering synergistic effect between corrosion and wear, the contribution of wear-induced-corrosion to total material loss is not very high although corrosion rate is greatly accelerated by friction. The fraction of corrosion-induced-wear to the total material loss is high and in the range of 14.6%-20.5% under all sliding conditions.展开更多
建立了微波消解-电感耦合等离子体发射光谱法同时测定哈氏C-276合金中Cr、Fe、Mo、W元素含量的分析方法.采用10 m L HCl-HNO3-HF(体积比为10:1:1)混合酸溶解试样.研究了合金不同溶解方式、元素谱线的选择、背景校正等试验条件,并对仪器...建立了微波消解-电感耦合等离子体发射光谱法同时测定哈氏C-276合金中Cr、Fe、Mo、W元素含量的分析方法.采用10 m L HCl-HNO3-HF(体积比为10:1:1)混合酸溶解试样.研究了合金不同溶解方式、元素谱线的选择、背景校正等试验条件,并对仪器分析参数进行了优化,确定了最佳的试验条件,各元素分析谱线依次为Cr2 67.716 nm、Fe 238.204 nm、Mo 202.031 nm、W 209.712 nm,建立的校准曲线各元素相关系数均在0.999 5以上.实际样品分析中,加标回收率为97.8%~102.7%,重复测定结果的相对标准偏差小于1.64%(n=6),试验测定结果与镍基标准样品标准值做对照,结果表明方法准确、快速,能够满足日常生产的检测要求.展开更多
Preparation of the second-generation high-tem- perature superconducting tape by ion beam-assisted depo- sition （IBAD） requires a flat metal substrate. In this work, the electrochemical polishing of long-length Haste...Preparation of the second-generation high-tem- perature superconducting tape by ion beam-assisted depo- sition （IBAD） requires a flat metal substrate. In this work, the electrochemical polishing of long-length Hastelloy C-276 alloy was studied, and its process parameters, characterized roughness and other properties were inves- tigated. A 10-meter-long Hastelloy C-276 alloy was pre- pared by electrochemical polishing. The following optimized processing parameters are obtained： temperature of 45 ℃, current density of 0.439 A.cm-2 and polishing time of 60 s. The average roughness value （Ra） of the surface is less than 5 nm （5 μm × 5 μm）, which was characterized by atomic force microscopy. This value sat- isfies the requirements for the further preparation of tran- sition-layer pair by the IBAD technology route.展开更多
基金Project(LSL-1310)supported by the Open Project of State Key Laboratory of Solid Lubrication,ChinaProject(51171059)supported by the National Natural Science Foundation of China
文摘A systematic investigation was carried out to discuss the corrosion and tribocorrosion behaviors of Hastelloy C276 alloy sliding against Al2O3 pin in artificial seawater, using a pin-on-disk tribometer integrated with a potentiostat for electrochemical control. The results show that the great decrease of open circuit potential and three orders of magnitude increase of corrosion current density occur caused by friction. There are clearly synergistic effect between corrosion and wear, resulting in corrosion-induced-wear and wear-induced-corrosion in tribocorrosion process. The contribution of pure mechanical wear to total material loss exceeds 70% in all sliding conditions, so mechanical wear is the dominant factor during tribocorrosion. For considering synergistic effect between corrosion and wear, the contribution of wear-induced-corrosion to total material loss is not very high although corrosion rate is greatly accelerated by friction. The fraction of corrosion-induced-wear to the total material loss is high and in the range of 14.6%-20.5% under all sliding conditions.
基金financially supported by the National Science Foundation of China (Nos.51571002,51401003)the Beijing Municipal Natural Science Foundation (Nos.2172008,KZ201310005003)
文摘Preparation of the second-generation high-tem- perature superconducting tape by ion beam-assisted depo- sition （IBAD） requires a flat metal substrate. In this work, the electrochemical polishing of long-length Hastelloy C-276 alloy was studied, and its process parameters, characterized roughness and other properties were inves- tigated. A 10-meter-long Hastelloy C-276 alloy was pre- pared by electrochemical polishing. The following optimized processing parameters are obtained： temperature of 45 ℃, current density of 0.439 A.cm-2 and polishing time of 60 s. The average roughness value （Ra） of the surface is less than 5 nm （5 μm × 5 μm）, which was characterized by atomic force microscopy. This value sat- isfies the requirements for the further preparation of tran- sition-layer pair by the IBAD technology route.
