Due to the presence of graphite flake cascades, the real graphite anode of Li-ion battery shows non-iso- tropic characteristic. The present work developed an ellipsoid-based simulated annealing method and numeri- call...Due to the presence of graphite flake cascades, the real graphite anode of Li-ion battery shows non-iso- tropic characteristic. The present work developed an ellipsoid-based simulated annealing method and numeri- cally reconstructed the three-dimensional microstructure of a graphite anode. The reconstructed anode is a composite of three clearly distinguished phases： pore （or electrolyte）, graphite, and solid additives, well representing the non- isotropic heterogeneous characteristic of real graphite anode. Characterization analysis of the reconstructed electrode gives information such as the connectivity of individual phase, the specific interracial area between solid and pore phase, and the pore size distribution. The effects of the ellipsoid size on the structural characteristics of graphite anode were particularly studied. As the size of the ellipsoidal particle slightly increases, the average pore diameter increases and as a result the specific interfacial area between the solid and pore phase in the reconstructed area decreases; compared with the equatorial radius, the polar radius of ellipsoidal graphite particles has more sig- nificant influence on the characteristics of electrode microstructure.展开更多
Al alloy matrix composites reinforced with copper-coated graphite particle have been prepared by melt stirring process in this work.The effect of the addition of Mg on distribution of the graphite particles has been i...Al alloy matrix composites reinforced with copper-coated graphite particle have been prepared by melt stirring process in this work.The effect of the addition of Mg on distribution of the graphite particles has been investigated.Scanning electron microscopy （SEM） was used to observe the micro-morphology of Al alloy matrix composites reinforced with graphite particles.Meanwhile,the content of graphite was analyzed in the different position of casting by dissolution method and the mechanical properties of the composites were detected.The results show that the content of graphite increase with increasing Mg content;the graphite particles distribute uniformly in the particle reinforced metal matrix composites （PMMC） with 0.6 wt pct Mg;however,the agglomeration of the graphite particles is observed obviously in the matrix when Mg content is more than 1.0 wt pct.In addition,the proper Mg addition amount is beneficial to enhance the mechanical properties of the graphite particles reinforced Al alloy matrix composites and the abrasion resistance of the materials due to a reduce friction coefficient.展开更多
The electromagnetic-mechanical stirring technology was used to prepare QTi3.5-15/graghite slurry. The distribution of graphite particies in QTi3.5-15/graghite slurry was studied using cold quenching method. The result...The electromagnetic-mechanical stirring technology was used to prepare QTi3.5-15/graghite slurry. The distribution of graphite particies in QTi3.5-15/graghite slurry was studied using cold quenching method. The results show that solid fraction of QTi3.5-15/graphite slurry increases with the decreasing of stirring temperature. There is a linear relationship between solid fraction and stirring temperature. With the increasing of solid fraction, the distribution of graphite particies in slurry becomes uniform gradually. When the solid fraction is larger than 45%, the rising of graphite particies in slurry can be restricted, and QTi3.5-15/graghite slurry with uniform distribution of graphite particies can be prepared.展开更多
基金supported by the Key Scientific Development Project of Guangdong Province(2015A030308019)the Guangzhou Scientific and Technological Development Plan(2014J4100217)the Hundred Talents Program of Chinese Academy of Sciences
文摘Due to the presence of graphite flake cascades, the real graphite anode of Li-ion battery shows non-iso- tropic characteristic. The present work developed an ellipsoid-based simulated annealing method and numeri- cally reconstructed the three-dimensional microstructure of a graphite anode. The reconstructed anode is a composite of three clearly distinguished phases： pore （or electrolyte）, graphite, and solid additives, well representing the non- isotropic heterogeneous characteristic of real graphite anode. Characterization analysis of the reconstructed electrode gives information such as the connectivity of individual phase, the specific interracial area between solid and pore phase, and the pore size distribution. The effects of the ellipsoid size on the structural characteristics of graphite anode were particularly studied. As the size of the ellipsoidal particle slightly increases, the average pore diameter increases and as a result the specific interfacial area between the solid and pore phase in the reconstructed area decreases; compared with the equatorial radius, the polar radius of ellipsoidal graphite particles has more sig- nificant influence on the characteristics of electrode microstructure.
基金supported financially by the National Natural Science Foundation of China (No. 50774021)the Ministry of Science and Technology of China (No.2008AA03Z512)
文摘Al alloy matrix composites reinforced with copper-coated graphite particle have been prepared by melt stirring process in this work.The effect of the addition of Mg on distribution of the graphite particles has been investigated.Scanning electron microscopy （SEM） was used to observe the micro-morphology of Al alloy matrix composites reinforced with graphite particles.Meanwhile,the content of graphite was analyzed in the different position of casting by dissolution method and the mechanical properties of the composites were detected.The results show that the content of graphite increase with increasing Mg content;the graphite particles distribute uniformly in the particle reinforced metal matrix composites （PMMC） with 0.6 wt pct Mg;however,the agglomeration of the graphite particles is observed obviously in the matrix when Mg content is more than 1.0 wt pct.In addition,the proper Mg addition amount is beneficial to enhance the mechanical properties of the graphite particles reinforced Al alloy matrix composites and the abrasion resistance of the materials due to a reduce friction coefficient.
基金This project was supported by the National Natural Science Foundation of China(No.50304001) the Beijing Jiaotong University Foundation.
文摘The electromagnetic-mechanical stirring technology was used to prepare QTi3.5-15/graghite slurry. The distribution of graphite particies in QTi3.5-15/graghite slurry was studied using cold quenching method. The results show that solid fraction of QTi3.5-15/graphite slurry increases with the decreasing of stirring temperature. There is a linear relationship between solid fraction and stirring temperature. With the increasing of solid fraction, the distribution of graphite particies in slurry becomes uniform gradually. When the solid fraction is larger than 45%, the rising of graphite particies in slurry can be restricted, and QTi3.5-15/graghite slurry with uniform distribution of graphite particies can be prepared.
