泡沫铜/低熔点合金复合相变材料凝固放热分析

为研究泡沫铜/低熔点合金(LMPA)复合相变材料在间歇放热工作环境下恢复至初始状态的能力及不同孔隙率泡沫铜的添加对其凝固放热过程的影响，通过数值模拟对比分析了47合金、正二十三烷与泡沫铜复合前后的凝固放热过程，并调节泡沫铜/47合金复合材料孔隙率计算模拟芯片温度在凝固放热过程中温度随时间变化曲线。结果表明:泡沫铜的添加对2类材料凝固过程均有促进作用，模拟芯片恢复至目标温度所需时间分别被缩短6.6%和47.7%。因体积潜热值的差距，泡沫铜/47合金凝固时需放出更多热量，恢复至目标温度的时间较长，是正二十三烷复合相变材料的1.52倍。随着孔隙率的增大，复合相变材料恢复至室温状态所用时长变化不大，考虑到孔隙率对相变热控过程中的影响，实际使用时应综合考虑。 

Solidification heat release of copper foam / low-melting-point alloy composite phase change material

In order to research the competence of the copper foam/low-melting-point alloy (LMPA) composite material to recover to the initial state in the intermittent exothermic working environment and the influence of the addition of copper foam with different porosity on the solidification exothermic process, this paper compares and analyzes the solidification exothermic process of 47 alloys and n-tricosane before and after compositing with copper foam through numerical simulation, and adjusts the porosity of the copper foam/47 alloy composite material to calculate the temperature change curve of the simulation chip temperature during the solidification exothermic process. The results show that the addition of copper foam can promote the solidification process of the two types of materials, and the time of the simulation chip to recover to the target temperature is shortened by 6.6% and 47.7%. Due to the difference in volume latent heat value, the copper foam/47 alloy needs to release more heat during solidification, and it takes longer to recover to the target temperature, which is 1.52 times that of the n-tricosane composite. With the increase of porosity, the time that is taken for the composite phase change material to return to room temperature does not change much. Considering the influence of porosity on the thermal control process of phase change, comprehensive consideration should be given to actual use.