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可膨胀石墨是制备膨胀石墨(EG)的先躯体,压柱成型会对其膨胀所得EG的激光消光性能产生影响。为了优化其成型参数,将先驱体可膨胀石墨(GIC)采用不同压强压制成药柱,对其热膨胀特性及膨胀后所得EG的膨胀体积(EV)、蠕虫形貌、微观结构以及对1.064μm激光的消光性能展开了研究。结果表明:相较于松散态,成型GIC先驱体所制备的EG蠕虫变细、变短,孔隙率降低;成型压强由0 MPa增至50 MPa,其EV由356 ml/g减小到216 ml/g,所得EG对1.064μm激光的质量消光截面σM由0.18 m2/g减小到0.04 m2/g,且在20~40 MPa时EV变化率仅为10.6%,σM变化率同样很小。显然,存在对EV及σM影响较小的压强范围,因此,在EG工程应用中,为满足尽可能大的装药密度,GIC成型可考虑选该压强范围的上限值。
Expandable graphite is the precursor for the preparation of expanded graphite (EG), which will affect the laser extinction properties of the expanded EG. In order to optimize the forming parameters, the precursors of expandable graphite (GIC) were compressed into pellets under different pressures. The thermal expansion characteristics and the expanded volume (EG), the morphology of worms, the microstructure of expanded EG, Extinction performance has been studied. The results showed that compared with the loose state, the EG worms prepared by forming GIC precursors became thinner and shorter and the porosity decreased. The forming pressure was increased from 0 MPa to 50 MPa, and the EV decreased from 356 ml / g to 216 ml / g, the mass extinction cross-section σM of 1.064μm laser obtained from EG decreased from 0.18 m2 / g to 0.04 m2 / g, and the EV change rate was only 10.6% at 20-40 MPa. Obviously, there is a pressure range that has a small effect on EV and σM. Therefore, in EG engineering applications, the upper limit of this pressure range can be considered for GIC molding in order to satisfy the largest possible charge density.