200-nm-thick Au interconnects on a quartz substrate were tested in-situ inside a dual-beam microscope by applying direct current, alternating current and alternating current with a small direct current component. The ...200-nm-thick Au interconnects on a quartz substrate were tested in-situ inside a dual-beam microscope by applying direct current, alternating current and alternating current with a small direct current component. The failure behavior of the Au interconnects under three kinds of electric currents were characterized in-situ by scanning electron microscopy. It is found that the formation of voids and subsequent growth perpendicular to the interconnect direction is the fatal failure mode for all the Au interconnects under three kinds of electric currents. The failure mechanism of the ultrathin metal lines induced by the electric currents was analyzed.展开更多
New-type magnesium alloy with prominent solubility and mechanical property lays foundation for preparing fracturing part in petroleum extraction.Herein,Mg-xZn-Zr-SiC alloy is prepared with casting strategy.Electrochem...New-type magnesium alloy with prominent solubility and mechanical property lays foundation for preparing fracturing part in petroleum extraction.Herein,Mg-xZn-Zr-SiC alloy is prepared with casting strategy.Electrochemical and compression tests are conducted to assess the feasibility as decomposable material.Morphology,composition,phase and distribution are characterized to investigate decomposition mechanism.Results indicate that floccule,substrate component and reticulate secondary phase are formed on as-prepared surface.Sample also acts out enhanced compression strength to maintain pressure and guarantee stability in dissolution process.Furthermore,as decomposition time and zinc content increase,couple corrosion intensifies,resulting in gradually enhanced decomposition rate.Rapid sample decomposition is mainly due to basal anode dissolution,micro particle exfoliation and poor decomposition resistance of corroding product.Such work shows profound significance in preparing new-type accessible alloy to ensure rapid dissolution of fracturing part and guarantee stable compression strength in oil-gas reservoir exploitation.展开更多
Hydrogenated amorphous carbon(a-C:H)films are capable of providing excellent superlubricating properties,which have great potential serving as self-lubricating protective layer for mechanical systems in extreme workin...Hydrogenated amorphous carbon(a-C:H)films are capable of providing excellent superlubricating properties,which have great potential serving as self-lubricating protective layer for mechanical systems in extreme working conditions.However,it is still a huge challenge to develop a-C:H films capable of achieving robust superlubricity state in vacuum.The main obstacle derives from the lack of knowledge on the influencing mechanism of deposition parameters on the films bonding structure and its relation to their self-lubrication performance.Aiming at finding the optimized deposition energy and revealing its influencing mechanism on superlubricity,a series of highly-hydrogenated a-C:H films were synthesized with appropriate ion energy,and systematic tribological experiments and structural characterization were conducted.The results highlight the pivotal role of ion energy on film composition,nanoclustering structure,and bonding state,which determine mechanical properties of highly-hydrogenated a-C:H films and surface passivation ability and hence their superlubricity performance in vacuum.The optimized superlubricity performance with the lowest friction coefficient of 0.006 coupled with the lowest wear rate emerges when the carbon ion energy is just beyond the penetration threshold of subplantation.The combined growth process of surface chemisorption and subsurface implantation is the key for a-C:H films to acquire stiff nanoclustering network and high volume of hydrogen incorporation,which enables a robust near-frictionless sliding surface.These findings can provide a guidance towards a more effective manipulation of self-lubricating a-C:H films for space application.展开更多
基金supported by the National Basic Research Program of China (No.2004CB619303)"The Hundred Talent Plan"of Chinese Academy of Sciencespartially by the National Natural Science Foundation of China (No.50571103).
文摘200-nm-thick Au interconnects on a quartz substrate were tested in-situ inside a dual-beam microscope by applying direct current, alternating current and alternating current with a small direct current component. The failure behavior of the Au interconnects under three kinds of electric currents were characterized in-situ by scanning electron microscopy. It is found that the formation of voids and subsequent growth perpendicular to the interconnect direction is the fatal failure mode for all the Au interconnects under three kinds of electric currents. The failure mechanism of the ultrathin metal lines induced by the electric currents was analyzed.
基金supported by the National Natural Science Foundation of China(No.51905417)China Postdoctoral Science Foundation(No.2020M670306).
文摘New-type magnesium alloy with prominent solubility and mechanical property lays foundation for preparing fracturing part in petroleum extraction.Herein,Mg-xZn-Zr-SiC alloy is prepared with casting strategy.Electrochemical and compression tests are conducted to assess the feasibility as decomposable material.Morphology,composition,phase and distribution are characterized to investigate decomposition mechanism.Results indicate that floccule,substrate component and reticulate secondary phase are formed on as-prepared surface.Sample also acts out enhanced compression strength to maintain pressure and guarantee stability in dissolution process.Furthermore,as decomposition time and zinc content increase,couple corrosion intensifies,resulting in gradually enhanced decomposition rate.Rapid sample decomposition is mainly due to basal anode dissolution,micro particle exfoliation and poor decomposition resistance of corroding product.Such work shows profound significance in preparing new-type accessible alloy to ensure rapid dissolution of fracturing part and guarantee stable compression strength in oil-gas reservoir exploitation.
基金The authors would like to thank Dongzhou ZHAN for technological support during friction experiment.This work was supported by the National Natural Science Foundation of China(Nos.51925506,51975314,51935006,and 51527901).
文摘Hydrogenated amorphous carbon(a-C:H)films are capable of providing excellent superlubricating properties,which have great potential serving as self-lubricating protective layer for mechanical systems in extreme working conditions.However,it is still a huge challenge to develop a-C:H films capable of achieving robust superlubricity state in vacuum.The main obstacle derives from the lack of knowledge on the influencing mechanism of deposition parameters on the films bonding structure and its relation to their self-lubrication performance.Aiming at finding the optimized deposition energy and revealing its influencing mechanism on superlubricity,a series of highly-hydrogenated a-C:H films were synthesized with appropriate ion energy,and systematic tribological experiments and structural characterization were conducted.The results highlight the pivotal role of ion energy on film composition,nanoclustering structure,and bonding state,which determine mechanical properties of highly-hydrogenated a-C:H films and surface passivation ability and hence their superlubricity performance in vacuum.The optimized superlubricity performance with the lowest friction coefficient of 0.006 coupled with the lowest wear rate emerges when the carbon ion energy is just beyond the penetration threshold of subplantation.The combined growth process of surface chemisorption and subsurface implantation is the key for a-C:H films to acquire stiff nanoclustering network and high volume of hydrogen incorporation,which enables a robust near-frictionless sliding surface.These findings can provide a guidance towards a more effective manipulation of self-lubricating a-C:H films for space application.
