Versatile liquid manipulating surfaces combining patternable and controllable wettability have recently motivated considerable attention owing to their significant advantages in droplet-solid impacting behaviors,micro...Versatile liquid manipulating surfaces combining patternable and controllable wettability have recently motivated considerable attention owing to their significant advantages in droplet-solid impacting behaviors,microdroplet self-removal,and liquid–liquid interface reaction applications.However,developing a facile and efficient method to fabricate these versatile surfaces remains an enormous challenge.In this paper,a strategy for the fabrication of liquid manipulating surfaces with patternable and controllable wettability on Polyimide(PI)film based on femtosecond laser thermal accumulation engineering is proposed.Because of its controllable micro-/nanostructures and chemical composition through adjusting the local thermal accumulation,the wettability of PI film can be tuned from superhydrophilicity(~3.6°)to superhydrophobicity(~151.6°).Furthermore,three diverse surfaces with patternable and heterogeneous wettability were constructed and various applications were successfully realized,including water transport,droplet arrays,and liquid wells.This work may provide a facile strategy for achieving patternable and controllable wettability efficiently and developing multifunctional liquid steering surfaces.展开更多
The rheological behavior of a low epoxy resin system-SR8100/SD8734 for RTM in aviation industry was studied with viscosity experiments. The dual-Arrhenius rheological model and the improved engineering viscosity model...The rheological behavior of a low epoxy resin system-SR8100/SD8734 for RTM in aviation industry was studied with viscosity experiments. The dual-Arrhenius rheological model and the improved engineering viscosity model were introduced and compared with the experimental data. The results indicated that the viscosity in the earlier stage calculated by dual-Arrhenius model matched the experimental data. As rising to 400 m.Pas, the viscosity calculated by the improved engineering model was closer to the experimental data. The processing windows of the resin system for RTM were determined by combining the two models, which could predict the theological behavior of the resin system in a more credible way. 30-45 ℃ was the optimum processing temperature.展开更多
We evaluate the effects of the holes geometry drilled by a femtosecond laser on a stainless alloy with various defocused irradiation time, which ranges from 0 min to 1 h. The laser ablation efficiency is increased by ...We evaluate the effects of the holes geometry drilled by a femtosecond laser on a stainless alloy with various defocused irradiation time, which ranges from 0 min to 1 h. The laser ablation efficiency is increased by a factor of3 when the irradiation time is elevated from 0 to 30 min. Also, the morphology of the hole is observed by a scanning electron microscope, where the result indicates that the defocused irradiation time has a significant influence on the morphology changes. The reason for such changes is discussed based on the pretreatment effect and the confined plasma plume. As an application example, the microchannel is fabricated by a femtosecond laser combined with the defocused irradiation to demonstrate the advantage of the proposed method in fabricating functional structures.展开更多
A fused silica glass micro-channel can be formed by chemical etching after femtosecond laser irradiation, and the successful etching probability is only 48%. In order to improve the micro-channel fabrication success p...A fused silica glass micro-channel can be formed by chemical etching after femtosecond laser irradiation, and the successful etching probability is only 48%. In order to improve the micro-channel fabrication success probability,the method of processing a high-temperature lattice by a femtosecond laser pulse train is provided. With the same pulse energy and scanning speed, the success probability can be increased to 98% by optimizing pulse delay.The enhancement is mainly caused by the nanostructure, which changes from a periodic slabs structure to some intensive and loose pore structures. In this Letter, the optimum pulse energy distribution ratio to the etching is also investigated.展开更多
基金This research is supported by National Natural Science Foundation of China(Nos.52075557,51805553)Natural Science Foundation of Hunan Province(No.2021JJ20067)+1 种基金The Science and Technology Innovation Program of Hunan Province(No.2021RC3011)Open access funding provided by Shanghai Jiao Tong University
文摘Versatile liquid manipulating surfaces combining patternable and controllable wettability have recently motivated considerable attention owing to their significant advantages in droplet-solid impacting behaviors,microdroplet self-removal,and liquid–liquid interface reaction applications.However,developing a facile and efficient method to fabricate these versatile surfaces remains an enormous challenge.In this paper,a strategy for the fabrication of liquid manipulating surfaces with patternable and controllable wettability on Polyimide(PI)film based on femtosecond laser thermal accumulation engineering is proposed.Because of its controllable micro-/nanostructures and chemical composition through adjusting the local thermal accumulation,the wettability of PI film can be tuned from superhydrophilicity(~3.6°)to superhydrophobicity(~151.6°).Furthermore,three diverse surfaces with patternable and heterogeneous wettability were constructed and various applications were successfully realized,including water transport,droplet arrays,and liquid wells.This work may provide a facile strategy for achieving patternable and controllable wettability efficiently and developing multifunctional liquid steering surfaces.
基金Funded by the Freedom Explore Program of Central South University(No.721500254)the Hunan Provincial Innovation Foundation for Postgraduate(No.CX2012B052)
文摘The rheological behavior of a low epoxy resin system-SR8100/SD8734 for RTM in aviation industry was studied with viscosity experiments. The dual-Arrhenius rheological model and the improved engineering viscosity model were introduced and compared with the experimental data. The results indicated that the viscosity in the earlier stage calculated by dual-Arrhenius model matched the experimental data. As rising to 400 m.Pas, the viscosity calculated by the improved engineering model was closer to the experimental data. The processing windows of the resin system for RTM were determined by combining the two models, which could predict the theological behavior of the resin system in a more credible way. 30-45 ℃ was the optimum processing temperature.
基金Projects(52075557,51805553) supported by the National Natural Science Foundation of ChinaProject(ZZYJKT2019-12) supported by the Project of State Key Laboratory of High Performance Complex Manufacturing,China。
基金supported by the National Natural Science Foundation of China(NSFC)(Nos.91323301and 51505505)the Fundamental Research Funds for the Central Universities of Central South University
文摘We evaluate the effects of the holes geometry drilled by a femtosecond laser on a stainless alloy with various defocused irradiation time, which ranges from 0 min to 1 h. The laser ablation efficiency is increased by a factor of3 when the irradiation time is elevated from 0 to 30 min. Also, the morphology of the hole is observed by a scanning electron microscope, where the result indicates that the defocused irradiation time has a significant influence on the morphology changes. The reason for such changes is discussed based on the pretreatment effect and the confined plasma plume. As an application example, the microchannel is fabricated by a femtosecond laser combined with the defocused irradiation to demonstrate the advantage of the proposed method in fabricating functional structures.
基金supported by the National Natural Science Foundation of China(Nos.51475482,51475481,51335011,and 91323301)the Fundamental Research Funds for the Central Universities of Central South University
文摘A fused silica glass micro-channel can be formed by chemical etching after femtosecond laser irradiation, and the successful etching probability is only 48%. In order to improve the micro-channel fabrication success probability,the method of processing a high-temperature lattice by a femtosecond laser pulse train is provided. With the same pulse energy and scanning speed, the success probability can be increased to 98% by optimizing pulse delay.The enhancement is mainly caused by the nanostructure, which changes from a periodic slabs structure to some intensive and loose pore structures. In this Letter, the optimum pulse energy distribution ratio to the etching is also investigated.
