中文摘要：

为了避免金属/陶瓷复合散热片两相共烧，并减小因两相热膨胀系数不同而造成在使用过程中的开裂失效问题，采用水基Al2O3陶瓷浆料在低温下进行多层流延，经定向冷冻、低温干燥及烧结工艺，制备出具有小孔径、直通孔结构的片状Al2O3多孔陶瓷。研究了浆料固体含量和冷冻温度对多孔陶瓷片孔隙率和孔尺寸的影响，观察了孔的微观形貌并测试了其热疲劳性能。结果表明：随着浆料固体含量从30% （质量分数）增加到40%，多孔陶瓷片的孔隙率（体积分数）从62.1%减小至51.4%，随着冷冻温度从–15 ℃降低至–45 ℃，多孔陶瓷片孔道尺寸逐渐减小；固体含量为40%、冷冻温度为–45 ℃的多孔陶瓷片在热疲劳实验中裂纹出现最晚，达到695次，其热疲劳性能最好；多层低温流延法制备的多孔陶瓷片层间孔道相互连通。

英文摘要：

In order to avoid co-firing and reduce the cracking failure caused by different expansion rates of metal/ceramic composite heat sink, a method for the production of highly aligned porous ceramics substrate by multilayer freeze-tape-casting process with aqueous alumina slurry was proposed. The effects of solid content and freezing temperature on the porosity and pore size were investigated, and the pore morphology （e.g., degree of pore alignment, pore size and interconnection between the pores） of the fabricated samples was characterized by ？eld emission scanning electron microscopy. Furthermore, the thermal fatigue properties of porous ceramic substrate were also examined. The results show that the porosity （volume fraction） gradually decreases from 62.1% to 51.4% with the increase of solid content （mass fraction） from 30% to 40%, and the pore size decreases gradually with the decrease of freezing temperature from –15 ℃ to –45 ℃. The optimum thermal fatigue properties were obtained at the solid content of 40% and the freezing temperature of –45 ℃. Also, the pore channels between the layers of ceramic substrate produced by multilayer freeze-tape-casting process could be connected.