Preparation For And Study Of Microstructures Of Mesocarbon Alloy Doped Ti/Cu Or Ti/Ni

Preparation and microstructures of carbonaceous mesophases added withalloy elements were studied in this paper. Based on a deeply understanding ofthe current developing states of the carbonaceous mesophases, the effect ofpreparation parameters on the microstructures, morphology and thermal stabilityof the carbonaceous mesophases alloyed with Ti/Cu or Ti/Ni were investigated.The metastable mesophase carbon alloys added with different metallicelements, including Ti/Cu,Ti/Ni into the carbonaceous mesophases werefabricated on graphite by using mechanical alloying, elevated temperatureand/or pressure synthesis techniques and vacuum annealing. Also, influencefactors of fabrication, microstructure of carbon alloy, graphitization degree,average grain size, morphology and the thermal stability of carbon alloys wereanalyzed.The effects of the ball milling time, the type and content of added metallicelements on the microstructure and morphology of the carbon alloys wereinvestigated in the process of fabricating the mesophase carbon alloys. Theeffects of different pressure with the same temperature 800℃ and differenttemperature with the same pressure 5GPa on microstructure, graphitizationdegree, average grain size and morphology of he carbon alloys were studied.The endothermic peak, the exothermic peak and the phase-transitiontemperature during vacuum annealing were discussed too. The structural characteristic of carbon alloy was analyzed by using XRD,while microstructure and content by using SEM and EDS, morphology by usingTEM and thermal stability by using DSC. The results show that, the mechanical alloying treatment results in a largerinterlayer distance (d002) for the mesophas. That is too say, it makes thenon-order degree of the mesophase bigger. Moreover, it also results in lowergraphitization degree and smaller average crystallite diameter. The addition ofthe metallic elements can inhibit the structural amorphouzation caused by theball milling. With prolonged ball milling time, the morphology of the mesophasecarbon alloy is changed into non-order shape from regular ball shape, thenmulti-layer shape. The high temperature and high pressure treatment at 800℃with increased pressure results in a larger interlayer distance (d002) for thecarbon alloy added Ti/Cu, which also lower the graphitization degree andincrease the non-order degree of the carbon alloy. With the temperatureincreased under the same pressure, the average crystallite diameter of the carbonalloy is smaller and symmetrical. With ball milling time prolongs, the thermalstability of the carbon alloy changes, which is indicated by the endothermic peakand the exothermic peak in the DSC-TGA curves.