Effect of electrolyte on mechanical properties of AZ31B Mg alloy in electrolytic plasma processing

Coatings on Mg alloys were prepared using NaOH + Na2SiO3 as basic electrolyte containing electrolyte of Na2SiF6 or NaF. EPP treatment was carried out on AZ31 Mg alloys matrix under a hybrid voltage of AC of 200 V combined with DC of 260 V for 30 min. Structural and morphological analyses of ceramic coatings were analyzed by XRD and SEM. Wear and hardness of coatings were measured by pin-on disk test and Vickers hardness test. The coatings formed in Na2SiF6 and NaF electrolytes were mainly composed of MgO and Mg2SiO4. The measured micro-hardness of coating formed in Na2SiF6 electrolyte was found to be over HV 1100, while, coating formed in NaF electrolyte possessed micro-hardness of HV ~900. These results show that the mechanical properties of AZ31 B Mg alloys can be enhanced by the proper selection of electrolyte agent.

Ionic Polymer-Metal Composite Electro-Active Nano-biopolymer Actuator

This research article introduces an electroactive actuator based on sulfonated chitosan(SCS),ionic liquid and graphene oxide(GO).To maintain the biocompatibility of the chitosan and to increase the actuation performance,a biocompatible ionic liquid such as ethyl,methylimidazolium-trifluoro methane sulfonated(EMI-TFMS)as mobile solvent was used for dry-type actuation.And GO-reinforced SCS films obtained through a simple solvent casting method were extensively investigated because of better electro-chemo-mechanical properties and higher actuation performances.Field-emission scanning electron microscope(FE-SEM),X-ray diffraction(XRD),Fourier transformer infrared spectroscopy(FT-IR),and Raman spectra were used to investigate the interaction mechanism between GO and SCS.The harmonic and step responses of GO and SCS composite actuator show large bending deformations under low electric voltage.

Sand-polished Kapton film and aluminum as source of electron transfer triboelectric nanogenerator through vertical contact separation mode

Contact electrification is a direct triboelectrification method for producing current through charge transfer when two different differentiated materials have brought into contact.For the first time,we developed a simple triboelectric nanogenerator(TENG)where the electronic charges were realized through contact separation mode between sand-polished Kapton(SPK)and Al surface.Here,we demonstrated the energetic interfacial contact between these surfaces and observed satisfactory output performance.The novel SPK-TENG produced 40 V and 2.8μA,of open-circuit voltages(V_(oc))and short-circuit currents(Isc)at 4 Hz,respectively.Mainly,the SPK-TENG was dramatically increased up the performance of TENG,up to 40% of V_(oc) and 42% of I_(sc),with respect to the Kapton film because the mobility of electrons is very high on the device surface compared to the other pristine Kapton film.The fabricated SPK-TENGs were good candidates for satisfying the need for alternative contact separation mode TENGs.