超轻材料是一类密度小于10 mg/cm^3的新型材料,具有良好的比强度和比刚度,是优异的物理化学性质和结构性能的统一体。随着人们对超轻材料强大性能的认识,国内外许多课题组都相继开展了对超轻材料的研究,并取得了一系列的成果。现有的超轻材料已经涵盖了硅系、金属及其氧化物、陶瓷、高分子聚合物、新型碳材料及其复合物等各类成分。超轻材料具有声吸收、能量吸收、减震缓冲、热绝缘等性能,在航空航天领域具有重要作用。超轻材料的性能主要取决于它的结构和组成材料的固体成分的性能,比如材料中孔隙的分布以及固体本身的硬度及强度都对性能有着重要的影响。本文根据材料结构的不同,将超轻材料分为气凝胶、泡沫材料、微点阵材料三类。本文对近年来超轻材料的材质及制备方法进行了简要的综述,并通过对各种材料的比较就该领域未来的发展进行了展望。
Ultralight materials are a kind of novel materials whose densities are less than 10 mg/cm^3. These materials exhibit excellent physical properties,chemical properties and mechanical properties derived from both constituent and structure,which possess high specific strength and specific stiffness. With the excellent properties of ultralight materials,great effort has been devoted to studying ultralight materials. The components of the existed ultralight materials mainly include silica,metal and oxidizing materials,ceramic,polymers,carbon and compounds. Ultralight materials play an important role in the field of aerospace,due to their unique properties such as acoustic absorption,energy absorption,shock absorption and thermal insulation. The effective properties of ultralight materials are defined both by their cellular architecture and the properties of the solid,such as the spatial configuration of voids and solids,the stiffness and strength of solids. They all have significant influence on the properties of materials. In this review,ultralight materials are classified into three types by different structures: aerogel,foam and microlattice. Also,the fabrication methods and constituent of the ultralight materials created in recent work are summarized. In addition,The research prospects and directions of ultralight materials in the future are also briefly discussed by comparison of all kinds of materials.