Electrochemical tests were undertaken to determine the optimum conditions in seawater for corrosion protection of friction stir-welded 5083-O Al alloy.Polarization trend observations show that the limiting potential t...Electrochemical tests were undertaken to determine the optimum conditions in seawater for corrosion protection of friction stir-welded 5083-O Al alloy.Polarization trend observations show that the limiting potential that avoids the effects of hydrogen embrittlement is -1.6 V,corresponding to the crossover point between concentration polarization and activation polarization.However,the optimum protection potential is between -1.5 and -0.7 V since the current density at these values is low in the potentiostatic tests.When a galvanic cell is formed in the seawater,the welds exhibit electrochemically stable trends.Welded parts in galvanic tests with various area ratios are stable and have excellent anticorrosion characteristics.展开更多
Graphene oxide and silver nanowires were bar coated onto polyethylene terephthalate (PET) substrates and then welded using an ultraviolet (UV)-assisted flash light irradiation process to achieve both high electric...Graphene oxide and silver nanowires were bar coated onto polyethylene terephthalate (PET) substrates and then welded using an ultraviolet (UV)-assisted flash light irradiation process to achieve both high electrical conductivity and low haze. The irradiation process connected adjacent silver nanowires by welding, while simultaneously reducing the graphene oxide to graphene. This process was performed using a custom W-assisted flash light welding system at room temperature under ambient conditions and was extremely rapid, with processing time of several milliseconds. The effects of varying the weight fractions of the silver nanowires and graphene oxide and of varying the W-assisted flash light welding conditions (light energy and pulse duration) were investigated. The surface morphologies of the welded silver nanowire/graphene films were analyzed using scanning electron microscopy. Optical characterizations, including transmittance and haze measurements, were also conducted using a spectrophotometer. To test their resistance to oxidation, the welded silver nanowire/graphene films were subjected to high temperature in a furnace (100 ℃), and their sheet resistances were measured every hour. The flash light welding process was found to yield silver nanowire/graphene films with high oxidation resistance, high conductivity (14.35 Ω·sq-1), high transmittance (93.46%), and low haze (0.9%). This material showed uniform temperature distribution when applied as a resistive heating film.展开更多
基金The MEST and KOTEF through the Human Resource Training Project for Regional Innovation
文摘Electrochemical tests were undertaken to determine the optimum conditions in seawater for corrosion protection of friction stir-welded 5083-O Al alloy.Polarization trend observations show that the limiting potential that avoids the effects of hydrogen embrittlement is -1.6 V,corresponding to the crossover point between concentration polarization and activation polarization.However,the optimum protection potential is between -1.5 and -0.7 V since the current density at these values is low in the potentiostatic tests.When a galvanic cell is formed in the seawater,the welds exhibit electrochemically stable trends.Welded parts in galvanic tests with various area ratios are stable and have excellent anticorrosion characteristics.
文摘Graphene oxide and silver nanowires were bar coated onto polyethylene terephthalate (PET) substrates and then welded using an ultraviolet (UV)-assisted flash light irradiation process to achieve both high electrical conductivity and low haze. The irradiation process connected adjacent silver nanowires by welding, while simultaneously reducing the graphene oxide to graphene. This process was performed using a custom W-assisted flash light welding system at room temperature under ambient conditions and was extremely rapid, with processing time of several milliseconds. The effects of varying the weight fractions of the silver nanowires and graphene oxide and of varying the W-assisted flash light welding conditions (light energy and pulse duration) were investigated. The surface morphologies of the welded silver nanowire/graphene films were analyzed using scanning electron microscopy. Optical characterizations, including transmittance and haze measurements, were also conducted using a spectrophotometer. To test their resistance to oxidation, the welded silver nanowire/graphene films were subjected to high temperature in a furnace (100 ℃), and their sheet resistances were measured every hour. The flash light welding process was found to yield silver nanowire/graphene films with high oxidation resistance, high conductivity (14.35 Ω·sq-1), high transmittance (93.46%), and low haze (0.9%). This material showed uniform temperature distribution when applied as a resistive heating film.