水蒸气气氛下铝锂合金反应特性及动力学分析

Kinetics analysis and reaction characteristics of aluminum-lithium alloys in water vapor

金属铝具有高的能量密度,为了研究铝的反应活化机制,利用热天平分别研究锂质量含量为0%、1%、2%、5%、10%、20%的铝样品在水蒸气气氛下的反应特性,采用单曲线积分法计算了铝、铝锂合金(锂质量分数分别为10%和20%)与水反应的动力学参数,并对铝锂合金与水蒸气的产物做XRD测试。结果表明,锂含量增大,样品最终增重也会提高;着火温度随锂含量增加而降低,当锂含量超过5%后,着火温度变化不大,约为380℃。通过以上实验计算得出,锂的添加降低了整体反应的表观活化能,促进了铝样品与水的反应。

Aluminum has a high energy density.In order to investigate the activation mechanism of aluminum powder reaction in water vapor,experiments were carried out on the thermobalance to study the reaction characteristics of aluminum samples with different content of lithium（ 0%,1%,2%,5%,10% and 20%） in water vapor.Single curve integral method was adopted to calculate kinetic parameter of the reaction of aluminum and aluminum-lithium alloy（ 10% and 20% lithium） with H2O.The reaction product of aluminum-lithium alloy with H2O was measured by XRD.The results show that the weight gain rate of samples increases as lithium content increases.The ignition temperature drops with the increase of lithium content.But when the lithium mass percent increases up to 5%,ignition temperature rarely increases,which keeps at about 380 ℃. Finally,the conclusion is that addition of lithium decreases the apparent activation energy and promotes the reactive activativity of aluminum powder with water.