To improve the properties of mullite-based thermal insulation materials typically prepared by foam-casting method, samples were heat treated under carbon monoxide atmosphere created by a carbon bed at 600 °C and 800 °C, respectively. The effects of reduction process on microstructure, pore size distribution, phase evolution, cold crushing strength (CCS), and thermal conductivity of the resultant materials were systematically studied. The results showed that the formation of high aspect ratio mullite whiskers and small amounts of glassy phases among whiskers during the reduction process are demonstrated as the key factors in improving the properties of the resultant materials. The mechanical properties are determined to be significantly enhanced for the binding effect of glassy phase among whiskers with soaking duration gradually increased to 48 h. And the lower thermal conductivity of samples treated for 24–48 h are mainly due to the high connectivity and lowered size of pores from the accumulation of high aspect ratio whiskers. Compared with samples treated at 800 °C, both the highest CCS (4.2 MPa) and minimum thermal conductivity (0.15 W/m K) were obtained in the sample heat treated at 600 °C for 48 h. Hence, it was demonstrated that the use of low-temperature reduction process could enhance the mechanical and thermal insulation properties of mullite-based thermal insulation materials.

为了改善通常通过泡沫浇铸法制备的莫来石基隔热材料的性能，分别在600℃和800℃的碳床所产生的一氧化碳气氛下对样品进行热处理。系统地研究了还原工艺对所得材料的微观结构，孔径分布，相演变，冷抗碎强度（CCS）和热导率的影响。结果表明，还原过程中高纵横比的莫来石晶须的形成和晶须之间少量的玻璃相被证明是改善所得材料性能的关键因素。晶须之间的玻璃态结合作用的机械性能被确定为显着增强，并且浸泡时间逐渐增加到48小时。处理24–48 h的样品的导热系数较低，主要是由于高纵横比晶须的堆积而导致的高连通性和减小的孔尺寸。与在800°C下处理的样品相比，在600°C下热处理48 h的样品均获得了最高的CCS（4.2 MPa）和最低的热导率（0.15 W / m K）。因此，证明了使用低温还原工艺可以增强莫来石基隔热材料的机械和隔热性能。在600°C热处理48 h的样品中获得15 W / m K）。因此，证明了使用低温还原工艺可以增强莫来石基隔热材料的机械和隔热性能。在600°C热处理48 h的样品中获得15 W / m K）。因此，证明了使用低温还原工艺可以增强莫来石基隔热材料的机械和隔热性能。