The low earth orbit, 100km~1000km from the ground, is the operation area of the meteorological satellite space station and other spacecraft. The space environment in this area is harsh, space radiation and cosmic rays will cause damage to electronic devices. Composite protective coating has become the inevitable trend of the development of protective coating materials for low-orbit spacecraft.

Boron carbide can absorb a large number of neutrons and won't form a radioactive isotope, at present has been widely used in the nuclear reactor neutron absorption material, in addition to its excellent neutron absorption ability, boron carbide has strong chemical stability, high temperature resistant to acid and alkali resistant low density chemical stability is good The proportion of light and other characteristics, is a kind of ideal spacecraft protective coating material.