3D numerical simulations of dynamical tensile response of hybrid carbon nanotube(CNT)and SiC nanoparticle reinforced AZ91D magnesium(Mg)based composites considering interface cohesion over a temperature range from 25 ...3D numerical simulations of dynamical tensile response of hybrid carbon nanotube(CNT)and SiC nanoparticle reinforced AZ91D magnesium(Mg)based composites considering interface cohesion over a temperature range from 25 to 300℃ were carried out using a 3D representative volume element(RVE)approach.The simulation predictions were compared with the experimental results.It is clearly shown that the overall dynamic tensile properties of the nanocomposites at different temperatures are improved when the total volume fraction and volume fraction ratio of hybrid CNTs to SiC nanoparticles increase.The overall maximum hybrid effect is achieved when the hybrid volume fraction ratio of CNTs to SiC nanoparticles is in the range from 7:3 to 8:2 under the condition of total volume fraction of 1.0%.The composites present positive strain rate hardening and temperature softening effects under dynamic loading at high temperatures.The simulation results are in good agreement with the experimental data.展开更多
The stir casting technique was used to fabricate aluminum2024matrix hybrid composites reinforced with SiC(5%,mass fraction)and red mud(5%-20%,mass fraction)particles.The developed composites were characterized by usin...The stir casting technique was used to fabricate aluminum2024matrix hybrid composites reinforced with SiC(5%,mass fraction)and red mud(5%-20%,mass fraction)particles.The developed composites were characterized by using scanning electron microscopy(SEM)and electron dispersive spectrum(EDS)techniques.Further,Taguchi’s approach of experimental design was used to examine the tensile strength of the hybrid composites(with minimum number of experiments).It was found that the reinforcing particles were well dispersed and adequately bonded in the hybrid composites.The density and porosity of the hybrid composites were reduced with the increase in reinforcement content.The tensile strength of the composites increased with the increase in the red mud content and the ageing time.The developed model indicated that the red mud content had the highest influence on the tensile strength response followed by the ageing time.Overall,it was found that Al2024/SiC/red mud composites exhibited superior tensile strength(about34%higher)in comparison to the Al2024alloy under optimized conditions.展开更多
Complex formation of cerium （Ⅲ） with l-phenyl-2,3-dimethylpyrazolone-5-azo-4-pyrogallole （L） in the presence and absence ofcetylpyridine chloride （CPC） was investigated. Homogeneous CeL- and mixed ligand CeL-CP...Complex formation of cerium （Ⅲ） with l-phenyl-2,3-dimethylpyrazolone-5-azo-4-pyrogallole （L） in the presence and absence ofcetylpyridine chloride （CPC） was investigated. Homogeneous CeL- and mixed ligand CeL-CPC compounds are formed at pH 6. Constants of stability of the complexes are （IgKD 5.15±0.02 （CeL）, 7.98±0.03 （CeL-CPC）. Ratio of reagents in composition of homogeneous is （1 ：2） and in different ligand it equals to （1：2：2）. Beer＇s law is observed in interval of concentration 1.12-11.2 μg/ml Ce. The technique for photometric determination of cerium was worked out in artificial mixture.展开更多
基金The authors are grateful for the financial supports from the National Natural Science Foundation of China(11672055,11272072).
文摘3D numerical simulations of dynamical tensile response of hybrid carbon nanotube(CNT)and SiC nanoparticle reinforced AZ91D magnesium(Mg)based composites considering interface cohesion over a temperature range from 25 to 300℃ were carried out using a 3D representative volume element(RVE)approach.The simulation predictions were compared with the experimental results.It is clearly shown that the overall dynamic tensile properties of the nanocomposites at different temperatures are improved when the total volume fraction and volume fraction ratio of hybrid CNTs to SiC nanoparticles increase.The overall maximum hybrid effect is achieved when the hybrid volume fraction ratio of CNTs to SiC nanoparticles is in the range from 7:3 to 8:2 under the condition of total volume fraction of 1.0%.The composites present positive strain rate hardening and temperature softening effects under dynamic loading at high temperatures.The simulation results are in good agreement with the experimental data.
文摘The stir casting technique was used to fabricate aluminum2024matrix hybrid composites reinforced with SiC(5%,mass fraction)and red mud(5%-20%,mass fraction)particles.The developed composites were characterized by using scanning electron microscopy(SEM)and electron dispersive spectrum(EDS)techniques.Further,Taguchi’s approach of experimental design was used to examine the tensile strength of the hybrid composites(with minimum number of experiments).It was found that the reinforcing particles were well dispersed and adequately bonded in the hybrid composites.The density and porosity of the hybrid composites were reduced with the increase in reinforcement content.The tensile strength of the composites increased with the increase in the red mud content and the ageing time.The developed model indicated that the red mud content had the highest influence on the tensile strength response followed by the ageing time.Overall,it was found that Al2024/SiC/red mud composites exhibited superior tensile strength(about34%higher)in comparison to the Al2024alloy under optimized conditions.
文摘Complex formation of cerium （Ⅲ） with l-phenyl-2,3-dimethylpyrazolone-5-azo-4-pyrogallole （L） in the presence and absence ofcetylpyridine chloride （CPC） was investigated. Homogeneous CeL- and mixed ligand CeL-CPC compounds are formed at pH 6. Constants of stability of the complexes are （IgKD 5.15±0.02 （CeL）, 7.98±0.03 （CeL-CPC）. Ratio of reagents in composition of homogeneous is （1 ：2） and in different ligand it equals to （1：2：2）. Beer＇s law is observed in interval of concentration 1.12-11.2 μg/ml Ce. The technique for photometric determination of cerium was worked out in artificial mixture.
