The invention provides a foamy carbon based heat-insulation
composite material with light weight and high strength. The foamy carbon based heat-insulation
composite material with light weight and high strength is characterized by comprising a base material foamy carbon, an SiC
coating and reticulated SiC nanowires, wherein a foamy
carbon skeleton is coated with the SiC
coating; three-dimensional pores are filled with the reticulated SiC nanowires,
porosity is 90%-95%, average
pore diameter is 50 nm-500 nm,
apparent density is 0.05-0.2 g / cm<3>, and
compressive strength is 5-15 MPa. Foamy carbon is flexible foamy carbon and is prepared from
melamine foam through high-temperature
pyrolysis, the
porosity is 99% or higher, and the average
pore diameter is 20-50 mu m; the thickness of the SiC
coating is 0.5-1 mu m, the
diameter of the SiC nanowires is 50-300 nm, the average length is 30-50 mu m, and all the SiC nanowires are prepared with a
chemical vapor deposition method. The light foamy carbon based heat-insulation
composite material with high strength has the advantages as follows: 1, the foamy
carbon skeleton is coated with SiC, so that
oxidation resistance of the composite material is improved; 2, the foamy
carbon skeleton is coated with SiC, and mechanical properties of the composite material are improved accordingly; 3, internal pores of foam are segmented by the SiC nanowires, the internal
pore diameter is reduced, and the heat
conductivity of the composite material is reduced.