采用自制的高温激光石墨化平台对聚丙烯腈(PAN)基碳纤维进行石墨化处理,分别在不同激光功率和不同牵伸力条件下制备了多种碳纤维实验样品,利用拉曼光谱和XRD射线衍射研究了不同条件下碳纤维样品的化学结构和微观结构.结果表明:在牵伸力不变时,随着激光功率的增大,碳纤维石墨化程度提高,当激光功率增大到一定值时,单方面继续提高激光功率对于提高碳纤维石墨化程度的影响将变小;在激光功率一定时,随着牵伸力的增大,石墨微晶尺寸Lc、La均逐渐增大,而d002和取向角逐渐减小,在激光石墨化过程中,施加一定的牵伸力可以促使碳纤维中的石墨微晶沿纤维轴方向择优取向,改善微晶尺寸、减少石墨微晶层间距、提高微晶堆砌层数.%The graphitization of PAN based carbon fibers was carried out on a self-made laser based high temperature graphitization platform.Serials of carbon fiber samples were prepared under different laser power and different traction conditions.Then the chemical structure and microcrystal structure of the samples were studied by Raman spectroscopy and X-ray diffraction (XRD) respectively.The results showed that if the stretching force remained constant,the graphitization degree of carbon fiber increased with the laser power.When the laser power reached a certain value,the increase of graphitization degree by solely increasing the laser power became less obvious.If the laser power remained constant,as the stretching force increased,the size of graphite crystallite Lc,Laincreased accordingly,while d002and the orientation angle reduced gradually.In the process of laser based graphitization of fabricating carbon fiber,exerting a certain stretching force can impel the graphite crystallite of carbon fiber to preferentially orient along the fiber axis,and finally the crystallite size is improved,and the spacing of graphite microcrystalline layer is reduced and the number of microcrystalline packing layers is increased.
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