High-purity copper(Cu) with excellent thermal and electrical conductivity, is crucial in modern technological applications, including heat exchangers, integrated circuits, and superconducting magnets. The current puri...High-purity copper(Cu) with excellent thermal and electrical conductivity, is crucial in modern technological applications, including heat exchangers, integrated circuits, and superconducting magnets. The current purification process is mainly based on the zone/electrolytic refining or anion exchange, however, which excessively relies on specific integrated equipment with ultra-high vacuum or chemical solution environment, and is also bothered by external contaminants and energy consumption. Here we report a simple approach to purify the Cu foils from 99.9%(3N) to 99.99%(4N) by a temperature-gradient thermal annealing technique, accompanied by the kinetic evolution of single crystallization of Cu.The success of purification mainly relies on(i) the segregation of elements with low effective distribution coefficient driven by grain-boundary movements and(ii) the high-temperature evaporation of elements with high saturated vapor pressure.The purified Cu foils display higher flexibility(elongation of 70%) and electrical conductivity(104% IACS) than that of the original commercial rolled Cu foils(elongation of 10%, electrical conductivity of ~ 100% IACS). Our results provide an effective strategy to optimize the as-produced metal medium, and therefore will facilitate the potential applications of Cu foils in precision electronic products and high-frequency printed circuit boards.展开更多
Adsorption and inhibition behavior of 2,5-bis(ethyldisulfanyl)-1,3,4-thiadiazole(DMTDA) and N-((6-methyl-1H-benzo[d][1,2,3]triazol-1-yl)methyl)-N-octyloctan-1-amine(EAMBA) as corrosion inhibitors contained in copper f...Adsorption and inhibition behavior of 2,5-bis(ethyldisulfanyl)-1,3,4-thiadiazole(DMTDA) and N-((6-methyl-1H-benzo[d][1,2,3]triazol-1-yl)methyl)-N-octyloctan-1-amine(EAMBA) as corrosion inhibitors contained in copper foil rolling oil have been investigated using gravimetric and electrochemical techniques. Meanwhile, scanning electron microscopy(SEM) and energy dispersive spectrometer(EDS) have been employed to observe the surface topography and analyze the components on copper foil. The results show that the rolling oil containing DMTDA and EAMBA can significantly decrease the dissolution rate and increase the inhibition efficiency of samples, especially in the case of best compounded rolling oil system. The SEM and EDS investigations also confirmed that the protection of the copper foil surface is achieved by strong adsorption of the molecules which can prevent copper from being corroded easily. Reactivity descriptors of the corrosion inhibitors have been calculated by the density functional theory(DFT) and the reactivity has been analyzed through the molecular orbital and Fukui indices. Active sites of inhibitor are mainly concentrated on the ring and the polar functional groups, and in the meanwhile, the distribution is helpful to form coordination and backbonding among molecules and then to form stable adsorption on the metal surface. And this work provides theoretical evidence for the selection of corrosion inhibitors contained in copper foil rolling oil.展开更多
The 2,5-bis（ethyldisulfanyl）-l,3,4-thiadiazole （T561）, benzotriazole （BTA）,1-N, N-bis （2-ethylhexyl） aminomethyl-4-methyl-lh-benzotriazole （IRGAMET39） and I-IN, N-bis （2-ethylhexyl） aminomethyl] methyl ben...The 2,5-bis（ethyldisulfanyl）-l,3,4-thiadiazole （T561）, benzotriazole （BTA）,1-N, N-bis （2-ethylhexyl） aminomethyl-4-methyl-lh-benzotriazole （IRGAMET39） and I-IN, N-bis （2-ethylhexyl） aminomethyl] methyl benzotriazole （TT- LX） have been evaluated as corrosion inhibitors used in rolling oil for cold rolling of copper foil. The MRS-10A four-ball friction and wear tests have been carried out to compare their tribological properties, and the lubricating performance of rolling oils has been studied through rolling experiments. The oil sample containing IRGAMET 39 has the same PB value as that one containing T561, with the coefficient of friction increased by 35.6% and wear scar diameter decreased by 4%. The minimum rolling gauge has been studied after rolling lubrication, but the results show that inhibitors have no effect on it. Scanning electron microscopy （SEM） and energy dispersive spectrometry （EDS） analyses have indicated that the inhibitor is adsorbed on the copper surface to prevent copper from being corroded easily. In addition, the LEXT OLS4000 laser confocal microscopy has been used to observe the foil surface which shows that the streaks of foil surface are clear, the scratches are shallow and the surface failure is improved effectively.展开更多
Copper foils with gradient structure in thickness direction and different roughnesses on two surfaces were fabricated by double rolling. The two surface morphologies of double-rolled copper foils are quite different, ...Copper foils with gradient structure in thickness direction and different roughnesses on two surfaces were fabricated by double rolling. The two surface morphologies of double-rolled copper foils are quite different, and the surface roughness values are 61 and 1095 nm, respectively. The roughness value of matt surface can meet the requirement for bonding the resin matrix with copper foils used for flexible printed circuit boards, thus may omit traditional roughening treatment; the microstructure of double-rolled copper foils demonstrates an obviously asymmetric gradient feature. From bright surface to matt surface in thickness direction, the average grain size first increases from 2.3 to 7.4 μm and then decreases to 3.6 μm; compared with conventional rolled copper foils, the double-rolled copper foils exhibit a remarkably increased bending fatigue life, and the increased range is about 16.2%.展开更多
基金Project supported by the Basic and Applied Basic Research Foundation of Guangdong Province,China(Grant Nos.2019A1515110302 and 2022A1515140003)the Key Research and Development Program of Guangdong Province,China(Grant Nos.2020B010189001,2021B0301030002,2019B010931001,and 2018B030327001)+5 种基金the National Natural Science Foundation of China(Grant Nos.52172035,52025023,52322205,51991342,52021006,51991344,52100115,11888101,92163206,12104018,and 12274456)the National Key Research and Development Program of China(Grant Nos.2021YFB3200303,2022YFA1405600,2018YFA0703700,2021YFA1400201,and 2021YFA1400502)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB33000000)the Pearl River Talent Recruitment Program of Guangdong Province,China(Grant No.2019ZT08C321)China Postdoctoral Science Foundation(Grant Nos.2020T130022 and 2020M680178)the Science and Technology Plan Project of Liaoning Province,China(Grant No.2021JH2/10100012).
文摘High-purity copper(Cu) with excellent thermal and electrical conductivity, is crucial in modern technological applications, including heat exchangers, integrated circuits, and superconducting magnets. The current purification process is mainly based on the zone/electrolytic refining or anion exchange, however, which excessively relies on specific integrated equipment with ultra-high vacuum or chemical solution environment, and is also bothered by external contaminants and energy consumption. Here we report a simple approach to purify the Cu foils from 99.9%(3N) to 99.99%(4N) by a temperature-gradient thermal annealing technique, accompanied by the kinetic evolution of single crystallization of Cu.The success of purification mainly relies on(i) the segregation of elements with low effective distribution coefficient driven by grain-boundary movements and(ii) the high-temperature evaporation of elements with high saturated vapor pressure.The purified Cu foils display higher flexibility(elongation of 70%) and electrical conductivity(104% IACS) than that of the original commercial rolled Cu foils(elongation of 10%, electrical conductivity of ~ 100% IACS). Our results provide an effective strategy to optimize the as-produced metal medium, and therefore will facilitate the potential applications of Cu foils in precision electronic products and high-frequency printed circuit boards.
基金the financial assistance provided by the National Natural Science Foundation of China (No. 51474025)the Cooperation Program between USTB and SINOPEC (No.112116)
文摘Adsorption and inhibition behavior of 2,5-bis(ethyldisulfanyl)-1,3,4-thiadiazole(DMTDA) and N-((6-methyl-1H-benzo[d][1,2,3]triazol-1-yl)methyl)-N-octyloctan-1-amine(EAMBA) as corrosion inhibitors contained in copper foil rolling oil have been investigated using gravimetric and electrochemical techniques. Meanwhile, scanning electron microscopy(SEM) and energy dispersive spectrometer(EDS) have been employed to observe the surface topography and analyze the components on copper foil. The results show that the rolling oil containing DMTDA and EAMBA can significantly decrease the dissolution rate and increase the inhibition efficiency of samples, especially in the case of best compounded rolling oil system. The SEM and EDS investigations also confirmed that the protection of the copper foil surface is achieved by strong adsorption of the molecules which can prevent copper from being corroded easily. Reactivity descriptors of the corrosion inhibitors have been calculated by the density functional theory(DFT) and the reactivity has been analyzed through the molecular orbital and Fukui indices. Active sites of inhibitor are mainly concentrated on the ring and the polar functional groups, and in the meanwhile, the distribution is helpful to form coordination and backbonding among molecules and then to form stable adsorption on the metal surface. And this work provides theoretical evidence for the selection of corrosion inhibitors contained in copper foil rolling oil.
基金financially supported by the National Natural Science Foundation of China (No.51274037)the Key Science and Technology Project of China (No.2011BAE23B00)the Cooperation Program between USTB and SINOPEC (No.112116)
文摘The 2,5-bis（ethyldisulfanyl）-l,3,4-thiadiazole （T561）, benzotriazole （BTA）,1-N, N-bis （2-ethylhexyl） aminomethyl-4-methyl-lh-benzotriazole （IRGAMET39） and I-IN, N-bis （2-ethylhexyl） aminomethyl] methyl benzotriazole （TT- LX） have been evaluated as corrosion inhibitors used in rolling oil for cold rolling of copper foil. The MRS-10A four-ball friction and wear tests have been carried out to compare their tribological properties, and the lubricating performance of rolling oils has been studied through rolling experiments. The oil sample containing IRGAMET 39 has the same PB value as that one containing T561, with the coefficient of friction increased by 35.6% and wear scar diameter decreased by 4%. The minimum rolling gauge has been studied after rolling lubrication, but the results show that inhibitors have no effect on it. Scanning electron microscopy （SEM） and energy dispersive spectrometry （EDS） analyses have indicated that the inhibitor is adsorbed on the copper surface to prevent copper from being corroded easily. In addition, the LEXT OLS4000 laser confocal microscopy has been used to observe the foil surface which shows that the streaks of foil surface are clear, the scratches are shallow and the surface failure is improved effectively.
基金financially support by the National Key Technology Research and Development Program of the Ministry of Science and Technology of China (No.2011BAE23B02)the Fundamental Research Funds for the Central Universities of China (No.FRF-TP-10-002B)
文摘Copper foils with gradient structure in thickness direction and different roughnesses on two surfaces were fabricated by double rolling. The two surface morphologies of double-rolled copper foils are quite different, and the surface roughness values are 61 and 1095 nm, respectively. The roughness value of matt surface can meet the requirement for bonding the resin matrix with copper foils used for flexible printed circuit boards, thus may omit traditional roughening treatment; the microstructure of double-rolled copper foils demonstrates an obviously asymmetric gradient feature. From bright surface to matt surface in thickness direction, the average grain size first increases from 2.3 to 7.4 μm and then decreases to 3.6 μm; compared with conventional rolled copper foils, the double-rolled copper foils exhibit a remarkably increased bending fatigue life, and the increased range is about 16.2%.
