The phase compositions and properties of Ti3SiC2-based composites with SiC addition of 5%-30% in mass fraction fabricated by in-situ reaction and hot pressing sintering were studied. SiC addition effectively prevented...The phase compositions and properties of Ti3SiC2-based composites with SiC addition of 5%-30% in mass fraction fabricated by in-situ reaction and hot pressing sintering were studied. SiC addition effectively prevented TiC synthesis but facilitated SiC synthesis. The Ti3SiC2/Ti C-SiC composite had better oxidation resistance when SiC added quantity reached 20% but poorer oxidation resistance with SiC addition under 15% than Ti3SiC2/TiC composite at higher temperatures. There were more than half of the original SiC and a few Ti3SiC2 remaining in Ti3SiC2/Ti C-SiC with 20% SiC addition, but all constituents in Ti3Si2/TiC composite were oxidized after 12 h in air at 1500 °C. The oxidation scale thickness of TS30, 1505.78 μm, was near a half of that of T,2715 μm, at 1500 °C for 20 h. Ti3SiC2/Ti C composite had a flexural strength of 474 MPa, which was surpassed by Ti3SiC2/TiC-SiC composites when SiC added amount reached 15%. The strength reached the peak of 518 MPa at 20% SiC added amount.展开更多
Wearable electronic devices have received increasing interests because of their excellent flexibility,stretchability,and human friendliness.As the core components,flexible strain sensors integrated with wide working r...Wearable electronic devices have received increasing interests because of their excellent flexibility,stretchability,and human friendliness.As the core components,flexible strain sensors integrated with wide working range,high sensitivity,and environment stability,especially in moisture or corrosive environments,remain a huge challenge.Herein,synergistic carbon nanotubes(CNTs)/reduced graphene oxide(rGO)dual conductive layer decorated elastic rubber band(RB)was successfully developed and treated with hydrophobic fumed silica(Hf-SiO_(2))for preparing superhydrophobic strain sensor.As expected,stable entangled CNTs layer and ultrasensitive microcracked rGO layer endow the sensor with extremely low detection limit(0.1%),high sensitivity(gauge factor is 685.3 at 482%strain),wide workable strain range(0–482%),fast response/recovery(200 ms/200 ms)and favorable reliability and reproducibility over 1000 cycles.Besides,the constructed Hf-SiO_(2) coating also makes the sensor exhibit excellent superhydrophobicity,self-cleaning property,and corrosion-resistance.As a proof of concept,our prepared high-performance strain sensor can realize the full-range monitoring of human motions and physiological signals even in the water environment,including pulse,vocalization,joint bending,running,and gesture recognition.Interestingly,it can also be knitted into a tactile electronic textile for spatial pressure distribution measurement.Thus,this study provides a universal technique for the preparation of high-performance strain sensors with great potential applications in the field of next-generation intelligent wearable electronics.展开更多
基金Project(51302206)supported by the National Natural Science Foundation of ChinaProject(2013JK0925)supported by Shaanxi Provincial Department of Education,China+1 种基金Project(SKLSP201308)supported by the State Key Laboratory of Solidification Processing in Northwestern Polytechnical University,ChinaProject supported by the State Scholarship Fund,China
文摘The phase compositions and properties of Ti3SiC2-based composites with SiC addition of 5%-30% in mass fraction fabricated by in-situ reaction and hot pressing sintering were studied. SiC addition effectively prevented TiC synthesis but facilitated SiC synthesis. The Ti3SiC2/Ti C-SiC composite had better oxidation resistance when SiC added quantity reached 20% but poorer oxidation resistance with SiC addition under 15% than Ti3SiC2/TiC composite at higher temperatures. There were more than half of the original SiC and a few Ti3SiC2 remaining in Ti3SiC2/Ti C-SiC with 20% SiC addition, but all constituents in Ti3Si2/TiC composite were oxidized after 12 h in air at 1500 °C. The oxidation scale thickness of TS30, 1505.78 μm, was near a half of that of T,2715 μm, at 1500 °C for 20 h. Ti3SiC2/Ti C composite had a flexural strength of 474 MPa, which was surpassed by Ti3SiC2/TiC-SiC composites when SiC added amount reached 15%. The strength reached the peak of 518 MPa at 20% SiC added amount.
基金supported by the National Natural Science Foundation of China(12072325)the National Key R&D Program of China(2019YFA0706802)the 111 Project(D18023)。
文摘Wearable electronic devices have received increasing interests because of their excellent flexibility,stretchability,and human friendliness.As the core components,flexible strain sensors integrated with wide working range,high sensitivity,and environment stability,especially in moisture or corrosive environments,remain a huge challenge.Herein,synergistic carbon nanotubes(CNTs)/reduced graphene oxide(rGO)dual conductive layer decorated elastic rubber band(RB)was successfully developed and treated with hydrophobic fumed silica(Hf-SiO_(2))for preparing superhydrophobic strain sensor.As expected,stable entangled CNTs layer and ultrasensitive microcracked rGO layer endow the sensor with extremely low detection limit(0.1%),high sensitivity(gauge factor is 685.3 at 482%strain),wide workable strain range(0–482%),fast response/recovery(200 ms/200 ms)and favorable reliability and reproducibility over 1000 cycles.Besides,the constructed Hf-SiO_(2) coating also makes the sensor exhibit excellent superhydrophobicity,self-cleaning property,and corrosion-resistance.As a proof of concept,our prepared high-performance strain sensor can realize the full-range monitoring of human motions and physiological signals even in the water environment,including pulse,vocalization,joint bending,running,and gesture recognition.Interestingly,it can also be knitted into a tactile electronic textile for spatial pressure distribution measurement.Thus,this study provides a universal technique for the preparation of high-performance strain sensors with great potential applications in the field of next-generation intelligent wearable electronics.
