石蜡/膨胀石墨复合相变材料控温电子散热器的性能

为了提高电子器件抗热冲击的能力、保证电子器件运行的可靠性和稳定性,以石蜡为相变储能材料、膨胀石墨为支撑材料,采用物理吸附法制备石蜡/膨胀石墨复合相变材料,将其应用于电子器件的热管理中,并通过模拟芯片实验研究了石蜡/膨胀石墨复合相变材料控温电子散热器的性能.结果表明:石蜡质量分数为90%的复合相变材料的导热系数相比于纯石蜡(0.3608 W/(m.K))提高了约4倍;相变材料填充于散热器中,可有效降低模拟芯片的升、降温速率,延长散热器的控温时间;当芯片发热功率为15和20W时,散热器填充复合相变材料后的控温时间较填充前分别提升了59%和20%,可降低电子器件因温度瞬间升高而烧坏的可能性,实现对电子器件的保护.

Performance of Temperature-Controlled Electronic Heat Sink with Composite Paraffin/Expanded Graphite Phase Change Material

In order to improve the capability of heat shock resistance of electronic devices and ensure the working reliability and stability of the devices,composite paraffin/expanded graphite PCM(Phase Change Material) was prepared via the physical adsorption,with paraffin as a phase-change energy-storage material and with expanded graphite as a supporting matrix.Then,the product was applied to the thermal management of electronic devices,and the performance of a temperature-controlled heat sink with the composite PCM was investigated by the experiments on a simulated electronic chip.The results show that the thermal conductivity of the composite PCM containing 90% of paraffin is about 5 times that of pure paraffin(0.360 8 W/(m·K)),that the PCM filled in the heat sink effectively reduces the heating and cooling rates of the simulated electronic chip and prolongs the temperature-controlling time,and that,with the filling of the composite PCM in the heat sink,the temperature-controlling time of the chip at the heating powers of 15 and 20 W increases by 59% and 20%,respectively,which reduces the po-ssibility of burning out of electronic chips due to sharp temperature rise and provides the protection of electronic devices.