▎ 摘　　要

NOVELTY - An ultra-low density solid material has a porous structure with pore diameter of 10 μm to 10 mm, where the porous structure is composed of solid material building unit, and the density of the ultra-low density solid material is 0.001-0.1 mg/cm3. USE - Ultra-low density solid material used as heat insulating material, deformation sensor, micro pressure sensor, ultra-high temperature electric heating material or electrode material (all claimed). ADVANTAGE - The ultra-low density solid material has density of 0.001-0.1 mg/cm3, where this density breaks the density record of world's lightest solid material publicly reported, and opens up a new frontier for human exploration of low-density solids. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for preparation of the ultra-low density solid material, which involves: (a) providing a solid material dispersion and adding a toughening agent to the solid material dispersion to obtain a mixed dispersion; (b) foaming the mixed dispersion by vacuum foaming and freezing to shape at low temperature; and (c) drying.